Move terrascript 2 to separate module

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/Environment.java

@@ -0,0 +1,158 @@
+package com.dfsek.terra.addons.terrascript.v2;
+
+import javax.annotation.Nullable;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.NonexistentSymbolException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.SymbolAlreadyExistsException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.SymbolTypeMismatchException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.Symbol.Function;
+import com.dfsek.terra.addons.terrascript.v2.Environment.Symbol.Variable;
+import com.dfsek.terra.addons.terrascript.v2.codegen.NativeFunction;
+
+
+public class Environment {
+    
+    private final Environment outer;
+    
+    private final boolean canAccessOuterVariables;
+    
+    private final Map<String, Symbol> symbolTable = new HashMap<>();
+    
+    private final boolean inLoop;
+    
+    private final int index;
+    
+    private int innerCount = 0;
+    
+    public final String name;
+    
+    private Environment(@Nullable Environment outer, boolean canAccessOuterVariables, boolean inLoop, int index) {
+        this.outer = outer;
+        this.canAccessOuterVariables = canAccessOuterVariables;
+        this.inLoop = inLoop;
+        this.index = index;
+        this.name = String.join("_", getNestedIndexes().stream().map(Object::toString).toList());
+        // Populate symbol tables with built-in Java implemented methods
+        NativeFunction.BUILTIN_FUNCTIONS.forEach((name, function) -> symbolTable.put(name, new Symbol.Function(function.getReturnType(), function.getParameterTypes(), this)));
+    }
+    
+    public static Environment global() {
+        return new Environment(null, false, false, 0);
+    }
+    
+    public Environment lexicalInner() {
+        return new Environment(this, true, inLoop, innerCount++);
+    }
+    
+    public Environment loopInner() {
+        return new Environment(this, true, true, innerCount++);
+    }
+    
+    public Environment functionalInner() {
+        return new Environment(this, false, inLoop, innerCount++);
+    }
+    
+    private List<Integer> getNestedIndexes() {
+        List<Integer> idxs = new ArrayList<>();
+        for (Environment env = this; env.outer != null; env = env.outer) {
+            idxs.add(0, env.index);
+        }
+        return idxs;
+    }
+    
+    public Environment outer() {
+        if(outer == null) throw new RuntimeException("Attempted to retrieve outer scope of global scope");
+        return outer;
+    }
+    
+    public Function getFunction(String id) throws NonexistentSymbolException, SymbolTypeMismatchException {
+        Function function;
+        Symbol symbol = symbolTable.get(id);
+        if(symbol == null) {
+            if(outer == null) throw new NonexistentSymbolException();
+            function = outer.getFunction(id);
+        } else {
+            if(!(symbol instanceof Function)) throw new SymbolTypeMismatchException();
+            function = (Function) symbol;
+        }
+        return function;
+    }
+    
+    /**
+     * Returns symbol table entry for a variable identifier, includes enclosing scopes in lookup.
+     * <br>
+     * Does not factor context of lookup, checks for order of declaration should be done while
+     * symbol tables are being populated.
+     *
+     * @param id identifier used in variable declaration
+     *
+     * @return variable symbol table entry
+     *
+     * @throws NonexistentSymbolException  if symbol is not declared in symbol table
+     * @throws SymbolTypeMismatchException if symbol is not a variable
+     */
+    public Variable getVariable(String id) throws NonexistentSymbolException, SymbolTypeMismatchException {
+        Variable variable;
+        Symbol symbol = symbolTable.get(id);
+        if(symbol == null) {
+            if(!canAccessOuterVariables || outer == null) throw new NonexistentSymbolException();
+            variable = outer.getVariable(id);
+        } else {
+            if(!(symbol instanceof Variable)) throw new SymbolTypeMismatchException();
+            variable = (Variable) symbol;
+        }
+        return variable;
+    }
+    
+    public void put(String id, Symbol symbol) throws SymbolAlreadyExistsException {
+        if(symbolTable.containsKey(id)) throw new SymbolAlreadyExistsException();
+        symbolTable.put(id, symbol);
+    }
+    
+    public static abstract class Symbol {
+        
+        public static class Function extends Symbol {
+            
+            public final Type type;
+            
+            public final List<Type> parameters;
+            
+            public final Environment scope;
+            
+            public Function(Type type, List<Type> parameters, Environment scope) {
+                this.type = type;
+                this.parameters = parameters;
+                this.scope = scope;
+            }
+        }
+        
+        
+        public static class Variable extends Symbol {
+            
+            public final Type type;
+            
+            public Variable(Type type) {
+                this.type = type;
+            }
+        }
+    }
+    
+    
+    public static class ScopeException extends RuntimeException {
+        
+        public static class SymbolAlreadyExistsException extends ScopeException {
+        }
+        
+        
+        public static class NonexistentSymbolException extends ScopeException {
+        }
+        
+        
+        public static class SymbolTypeMismatchException extends ScopeException {
+        }
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/ErrorHandler.java

@@ -0,0 +1,20 @@
+package com.dfsek.terra.addons.terrascript.v2;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+public class ErrorHandler {
+    
+    private final List<Exception> exceptions = new ArrayList<>();
+    
+    public void add(Exception e) {
+        exceptions.add(e);
+    }
+    
+    public void throwAny() throws Exception {
+        for(Exception e : exceptions) {
+            throw e;
+        }
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/TerraScript2Addon.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2;
+
+import com.dfsek.terra.addons.manifest.api.AddonInitializer;
+import com.dfsek.terra.api.Platform;
+import com.dfsek.terra.api.addon.BaseAddon;
+import com.dfsek.terra.api.inject.annotations.Inject;
+
+
+public class TerraScript2Addon implements AddonInitializer {
+    @Inject
+    private Platform platform;
+    
+    @Inject
+    private BaseAddon addon;
+    
+    @Override
+    public void initialize() {
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/Type.java

@@ -0,0 +1,97 @@
+package com.dfsek.terra.addons.terrascript.v2;
+
+import java.util.Optional;
+
+public interface Type {
+    
+    static Type fromString(String lexeme) throws TypeException {
+        return switch(lexeme) {
+            case "num" -> NUMBER;
+            case "int" -> INTEGER;
+            case "str" -> STRING;
+            case "bool" -> BOOLEAN;
+            case "()" -> VOID;
+            default -> throw new TypeException();
+        };
+    }
+    
+    java.lang.reflect.Type javaType();
+    
+    default boolean typeOf(Type type) {
+        return this.equals(type);
+    }
+    
+    static Optional<Type> from(Class<?> clazz) {
+        return Optional.ofNullable(
+                clazz == double.class ? NUMBER :
+                clazz == String.class ? STRING :
+                clazz == boolean.class ? BOOLEAN :
+                clazz == void.class ? VOID :
+                null);
+    }
+    
+    Type NUMBER = new Type() {
+        @Override
+        public java.lang.reflect.Type javaType() {
+            return double.class;
+        }
+        
+        @Override
+        public String toString() {
+            return "num";
+        }
+    };
+    
+    Type INTEGER = new Type() {
+        
+        @Override
+        public java.lang.reflect.Type javaType() {
+            return int.class;
+        }
+        
+        @Override
+        public String toString() {
+            return "int";
+        }
+    };
+    
+    Type STRING = new Type() {
+        
+        @Override
+        public java.lang.reflect.Type javaType() {
+            return String.class;
+        }
+        
+        @Override
+        public String toString() {
+            return "str";
+        }
+    };
+    
+    Type BOOLEAN = new Type() {
+        @Override
+        public java.lang.reflect.Type javaType() {
+            return boolean.class;
+        }
+        
+        @Override
+        public String toString() {
+            return "bool";
+        }
+    };
+    
+    Type VOID = new Type() {
+        @Override
+        public java.lang.reflect.Type javaType() {
+            return void.class;
+        }
+        
+        @Override
+        public String toString() {
+            return "()";
+        }
+    };
+    
+    class TypeException extends Exception {
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/CodegenType.java

@@ -0,0 +1,141 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen;
+
+import com.dfsek.terra.addons.terrascript.v2.Type;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilerBugException;
+
+import org.objectweb.asm.Opcodes;
+
+import java.util.Map;
+
+
+public class CodegenType {
+    
+    private final InstructionType instructionType;
+    
+    private final String descriptor;
+    
+    public CodegenType(InstructionType instructionType, String descriptor) {
+        this.instructionType = instructionType;
+        this.descriptor = descriptor;
+    }
+    
+    public InstructionType bytecodeType() {
+        return instructionType;
+    }
+    
+    public String getDescriptor() {
+        return descriptor;
+    }
+    
+    public static final CodegenType BOOLEAN_PRIMITIVE = new CodegenType(InstructionType.INTEGER, "Z");
+    
+    private static final Map<Type, CodegenType> TYPE_MAP = Map.of(
+        Type.BOOLEAN, BOOLEAN_PRIMITIVE,
+        Type.STRING, new CodegenType(InstructionType.OBJECT, "Ljava/lang/String;"),
+        Type.NUMBER, new CodegenType(InstructionType.DOUBLE, "D"),
+        Type.VOID, new CodegenType(InstructionType.VOID, "V")
+    );
+    
+    public static CodegenType codegenType(Type type) {
+        CodegenType out = TYPE_MAP.get(type);
+        if(out == null)
+            throw new CompilerBugException();
+        return out;
+    }
+    
+    public enum InstructionType {
+        DOUBLE {
+            @Override
+            public int slotSize() {
+                return 2;
+            }
+            
+            @Override
+            public int returnInsn() {
+                return Opcodes.DRETURN;
+            }
+            
+            @Override
+            public int loadInsn() {
+                return Opcodes.DLOAD;
+            }
+            
+            @Override
+            public int storeInsn() {
+                return Opcodes.DSTORE;
+            }
+        },
+        OBJECT {
+            @Override
+            public int slotSize() {
+                return 1;
+            }
+            
+            @Override
+            public int returnInsn() {
+                return Opcodes.ARETURN;
+            }
+            
+            @Override
+            public int loadInsn() {
+                return Opcodes.ALOAD;
+            }
+            
+            @Override
+            public int storeInsn() {
+                return Opcodes.ASTORE;
+            }
+        },
+        INTEGER {
+            @Override
+            public int slotSize() {
+                return 1;
+            }
+            
+            @Override
+            public int returnInsn() {
+                return Opcodes.IRETURN;
+            }
+            
+            @Override
+            public int loadInsn() {
+                return Opcodes.ILOAD;
+            }
+            
+            @Override
+            public int storeInsn() {
+                return Opcodes.ISTORE;
+            }
+        },
+        VOID {
+            @Override
+            public int slotSize() {
+                throw new UnsupportedOperationException();
+            }
+            
+            @Override
+            public int returnInsn() {
+                return Opcodes.RETURN;
+            }
+            
+            @Override
+            public int loadInsn() {
+                throw new UnsupportedOperationException();
+            }
+            
+            @Override
+            public int storeInsn() {
+                throw new UnsupportedOperationException();
+            }
+        };
+        
+        public abstract int slotSize();
+        
+        public abstract int returnInsn();
+        
+        public abstract int loadInsn();
+        
+        public abstract int storeInsn();
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/NativeFunction.java

@@ -0,0 +1,86 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen;
+
+import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.dfsek.terra.addons.terrascript.v2.Type;
+
+
+public interface NativeFunction {
+    Map<String, NativeFunction> BUILTIN_FUNCTIONS = new HashMap<>() {{
+        put("print", new StaticMethodOfStaticField(
+                "java/lang/System",
+                "out",
+                "java/io/PrintStream",
+                "println",
+                "(Ljava/lang/String;)V",
+                Type.VOID,
+                List.of(Type.STRING))
+           );
+        put("printNum", new StaticMethodOfStaticField(
+                "java/lang/System",
+                "out",
+                "java/io/PrintStream",
+                "println",
+                "(D)V",
+                Type.VOID,
+                List.of(Type.NUMBER))
+           );
+    }};
+    
+    void pushInstance(MethodVisitor method);
+    
+    void callMethod(MethodVisitor method);
+    
+    Type getReturnType();
+    
+    List<Type> getParameterTypes();
+    
+    class StaticMethodOfStaticField implements NativeFunction {
+        
+        private final String fieldOwner;
+        private final String fieldName;
+        private final String className;
+        private final String methodName;
+        private final String methodDescriptor;
+        private final Type returnType;
+        private final List<Type> parameters;
+        
+        // TODO - Use reflection to obtain these automatically
+        public StaticMethodOfStaticField(String fieldOwner, String fieldName, String className, String methodName, String methodDescriptor,
+                                         Type returnType, List<Type> parameters) {
+            this.fieldOwner = fieldOwner;
+            this.fieldName = fieldName;
+            this.className = className;
+            this.methodName = methodName;
+            this.methodDescriptor = methodDescriptor;
+            this.returnType = returnType;
+            this.parameters = parameters;
+        }
+        
+        @Override
+        public void pushInstance(MethodVisitor method) {
+            method.visitFieldInsn(Opcodes.GETSTATIC, fieldOwner, fieldName, "L" + className + ";");
+        }
+        
+        @Override
+        public void callMethod(MethodVisitor method) {
+            method.visitMethodInsn(Opcodes.INVOKEVIRTUAL, className, methodName, methodDescriptor, false);
+        }
+        
+        @Override
+        public Type getReturnType() {
+            return returnType;
+        }
+        
+        @Override
+        public List<Type> getParameterTypes() {
+            return parameters;
+        }
+        
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/TerraScript.java

@@ -0,0 +1,8 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen;
+
+
+public interface TerraScript {
+    
+    void execute();
+    
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/asm/DynamicClassLoader.java

@@ -0,0 +1,19 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen.asm;
+
+import com.dfsek.terra.api.structure.Structure;
+
+
+public class DynamicClassLoader extends ClassLoader {
+    public DynamicClassLoader(Class<?> clazz) {
+        super(clazz.getClassLoader());
+    }
+   
+    public Class<?> defineClass(String name, byte[] data) {
+        return defineClass(name, data, 0, data.length);
+    }
+    
+    @Override
+    protected Class<?> findClass(String name) throws ClassNotFoundException {
+        return Class.forName(name);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/asm/OpcodeAlias.java

@@ -0,0 +1,17 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen.asm;
+
+import org.objectweb.asm.Opcodes;
+
+
+public class OpcodeAlias {
+    public static int CMP_GREATER_THAN = Opcodes.IFGT;
+    public static int CMP_GREATER_EQUALS = Opcodes.IFGE;
+    public static int CMP_LESS_THAN = Opcodes.IFLT;
+    public static int CMP_LESS_EQUALS = Opcodes.IFLE;
+    public static int CMP_EQUALS = Opcodes.IFEQ;
+    public static int CMP_NOT_EQUALS = Opcodes.IFNE;
+    public static int BOOL_FALSE = Opcodes.IFEQ;
+    public static int BOOL_TRUE = Opcodes.IFNE;
+    public static int INTEGERS_EQUAL = Opcodes.IF_ICMPEQ;
+    public static int INTEGERS_NOT_EQUAL = Opcodes.IF_ICMPNE;
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/codegen/asm/TerraScriptClassGenerator.java

@@ -0,0 +1,557 @@
+package com.dfsek.terra.addons.terrascript.v2.codegen.asm;
+
+import com.dfsek.terra.addons.terrascript.v2.Type;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Assignment;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Binary;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Call;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Grouping;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Literal;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Unary;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Variable;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr.Void;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.Block;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.Break;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.Continue;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.Expression;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.For;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.FunctionDeclaration;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.If;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.NoOp;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.Return;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.VariableDeclaration;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt.While;
+
+import com.dfsek.terra.addons.terrascript.v2.codegen.CodegenType;
+import com.dfsek.terra.addons.terrascript.v2.codegen.CodegenType.InstructionType;
+import com.dfsek.terra.addons.terrascript.v2.codegen.NativeFunction;
+import com.dfsek.terra.addons.terrascript.v2.codegen.TerraScript;
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilerBugException;
+import com.dfsek.terra.addons.terrascript.v2.util.ASMUtil;
+import com.dfsek.terra.addons.terrascript.v2.parser.BinaryOperator;
+import com.dfsek.terra.addons.terrascript.v2.parser.UnaryOperator;
+import com.dfsek.terra.api.util.generic.pair.Pair;
+
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.Label;
+import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.commons.LocalVariablesSorter;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.ArrayDeque;
+import java.util.Deque;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+
+import static com.dfsek.terra.addons.terrascript.v2.parser.BinaryOperator.*;
+import static com.dfsek.terra.addons.terrascript.v2.parser.UnaryOperator.*;
+import static com.dfsek.terra.addons.terrascript.v2.util.ASMUtil.dynamicName;
+
+public class TerraScriptClassGenerator {
+    
+    private static final Class<?> TARGET_CLASS = TerraScript.class;
+    
+    private static final boolean DUMP = true;
+    
+    private int generationCount = 0;
+    
+    private final String debugPath;
+    
+    public TerraScriptClassGenerator(String debugPath) {
+        this.debugPath = debugPath;
+    }
+    
+    /**
+     *
+     * @param root Assumed to be semantically correct
+     * @return Generated TerraScript instance
+     * @throws IOException
+     */
+    public TerraScript generate(Block root) throws IOException {
+        String targetClassName = dynamicName(TARGET_CLASS);
+        String generatedClassName = targetClassName + "_GENERATED_" + generationCount;
+        
+        ClassWriter classWriter = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
+        
+        // Create class
+        classWriter.visit(Opcodes.V1_8, Opcodes.ACC_PUBLIC, generatedClassName, null, "java/lang/Object", new String[]{ targetClassName });
+       
+        // Generate constructor method
+        MethodVisitor constructor = classWriter.visitMethod(Opcodes.ACC_PUBLIC, "<init>", "()V", null, null);
+        constructor.visitCode();
+        constructor.visitVarInsn(Opcodes.ALOAD, 0); // Put this reference on stack
+        constructor.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
+        constructor.visitInsn(Opcodes.RETURN); // Void return
+        constructor.visitMaxs(0, 0);
+        constructor.visitEnd();
+        
+        // Generate execute method
+        String methodName = "execute";
+        // Extract method description
+        MethodExtractor extractor = new MethodExtractor(methodName);
+        new ClassReader(targetClassName).accept(extractor, 0);
+        String description = extractor.methodDescription;
+        int exeAcc = Opcodes.ACC_PUBLIC;
+        MethodVisitor executeMethod = classWriter.visitMethod(exeAcc, methodName, description, null, null);
+        executeMethod.visitCode(); // Start method body
+        new MethodBytecodeGenerator(classWriter, generatedClassName, executeMethod, exeAcc, description).generate(root); // Generate bytecode
+        // Finish up method
+        executeMethod.visitInsn(Opcodes.RETURN);
+        executeMethod.visitMaxs(0, 0);
+        executeMethod.visitEnd();
+        
+        // Finished generating class
+        classWriter.visitEnd();
+        
+        DynamicClassLoader loader = new DynamicClassLoader(TARGET_CLASS); // Instantiate a new loader every time so classes can be GC'ed when they are no longer used. (Classes cannot be GC'ed until their loaders are).
+        
+        generationCount++;
+        
+        byte[] bytecode = classWriter.toByteArray();
+        
+        Class<?> generatedClass = loader.defineClass(generatedClassName.replace('/', '.'), bytecode);
+        
+        if (DUMP) {
+            File dump = new File(debugPath + "/" + generatedClass.getSimpleName() + ".class");
+            dump.getParentFile().mkdirs();
+            try(FileOutputStream out = new FileOutputStream(dump)) {
+                out.write(bytecode);
+            } catch(IOException e) {
+                e.printStackTrace();
+            }
+        }
+        
+        try {
+            Object instance = generatedClass.getDeclaredConstructor().newInstance();
+            return (TerraScript) instance;
+        } catch(ReflectiveOperationException e) {
+            throw new Error(e); // Should literally never happen
+        }
+    }
+    
+    private static class MethodBytecodeGenerator implements TypedStmt.Visitor<Void>, TypedExpr.Visitor<Void> {
+        
+        private final ClassWriter classWriter;
+        
+        private final String className;
+        
+        private final MethodVisitor method;
+        
+        private final String descriptor;
+        
+        private final LocalVariablesSorter lvs;
+        
+        private final Map<String, Integer> lvTable = new HashMap<>();
+        
+        private final Deque<Pair<Label, Label>> loopStack = new ArrayDeque<>();
+        
+        public MethodBytecodeGenerator(ClassWriter classWriter, String className, MethodVisitor method, int access, String descriptor) {
+            this.classWriter = classWriter;
+            this.className = className;
+            this.method = method;
+            this.descriptor = descriptor;
+            this.lvs = new LocalVariablesSorter(access, descriptor, method);
+        }
+        
+        public void generate(Block root) {
+            this.visitBlockTypedStmt(root);
+            
+        }
+        
+        @Override
+        public Void visitBinaryTypedExpr(Binary expr) {
+            switch(expr.operator) {
+                case EQUALS, NOT_EQUALS, BOOLEAN_AND, BOOLEAN_OR, GREATER, GREATER_EQUALS, LESS, LESS_EQUALS -> pushComparisonBool(expr);
+                case ADD -> {
+                    pushBinaryOperands(expr);
+                    CodegenType codegenType = CodegenType.codegenType(expr.type);
+                    if(codegenType.bytecodeType() == InstructionType.DOUBLE)
+                        method.visitInsn(Opcodes.DADD);
+                    else if (Objects.equals(codegenType.getDescriptor(), "Ljava/lang/String;"))
+                        // TODO - Optimize string concatenation
+                        method.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "concat", "(Ljava/lang/String;)Ljava/lang/String;", false);
+                    else throw new RuntimeException("Could not generate bytecode for ADD binary operator returning type " + expr.type);
+                }
+                case SUBTRACT -> binaryInsn(expr, Opcodes.DSUB);
+                case MULTIPLY -> binaryInsn(expr, Opcodes.DMUL);
+                case DIVIDE -> binaryInsn(expr, Opcodes.DDIV);
+                default -> throw new RuntimeException("Unhandled binary operator " + expr.operator);
+            }
+            return null;
+        }
+        
+        @Override
+        public Void visitGroupingTypedExpr(Grouping expr) {
+            expr.expression.accept(this);
+            return null;
+        }
+        
+        @Override
+        public Void visitLiteralTypedExpr(Literal expr) {
+            if(CodegenType.codegenType(expr.type) == CodegenType.BOOLEAN_PRIMITIVE)
+                if ((boolean) expr.value) pushTrue(); else pushFalse();
+            else method.visitLdcInsn(expr.value);
+            return null;
+        }
+        
+        @Override
+        public Void visitUnaryTypedExpr(Unary expr) {
+            expr.operand.accept(this);
+            switch (expr.operator) {
+                case NOT -> invertBool();
+                case NEGATE -> method.visitInsn(Opcodes.DNEG);
+            }
+            return null;
+        }
+        
+        @Override
+        public Void visitCallTypedExpr(Call expr) {
+            if (NativeFunction.BUILTIN_FUNCTIONS.containsKey(expr.identifier)) {
+                NativeFunction function = NativeFunction.BUILTIN_FUNCTIONS.get(expr.identifier);
+                function.pushInstance(method);
+                expr.arguments.forEach(a -> a.accept(this));
+                function.callMethod(method);
+                return null;
+            }
+            expr.arguments.forEach(a -> a.accept(this));
+            List<Type> parameters = expr.arguments.stream().map(e -> e.type).toList();
+            method.visitMethodInsn(Opcodes.INVOKESTATIC, className, expr.scopedIdentifier, getFunctionDescriptor(parameters, expr.type), false);
+            return null;
+        }
+        
+        @Override
+        public Void visitVariableTypedExpr(Variable expr) {
+            Type varType = expr.type;
+            method.visitVarInsn(CodegenType.codegenType(varType).bytecodeType().loadInsn(), lvTable.get(expr.identifier));
+            return null;
+        }
+        
+        @Override
+        public Void visitAssignmentTypedExpr(Assignment expr) {
+            expr.rValue.accept(this);
+            Type type = expr.lValue.type;
+            method.visitVarInsn(CodegenType.codegenType(type).bytecodeType().storeInsn(), lvTable.get(expr.lValue.identifier));
+            return null;
+        }
+        
+        @Override
+        public Void visitVoidTypedExpr(Void expr) {
+            return null;
+        }
+        
+        @Override
+        public Void visitExpressionTypedStmt(Expression stmt) {
+            stmt.expression.accept(this);
+            return null;
+        }
+        
+        @Override
+        public Void visitBlockTypedStmt(Block stmt) {
+            stmt.statements.forEach(s -> s.accept(this));
+            return null;
+        }
+        
+        /**
+         * Writes function as a private static method of the current class
+         * @param stmt
+         * @return
+         */
+        @Override
+        public Void visitFunctionDeclarationTypedStmt(FunctionDeclaration stmt) {
+            List<Type> parameterTypes = stmt.parameters.stream().map(Pair::getRight).toList();
+            
+            int access = Opcodes.ACC_PRIVATE | Opcodes.ACC_STATIC;
+            
+            MethodVisitor method = classWriter.visitMethod(access, stmt.scopedIdentifier, getFunctionDescriptor(parameterTypes, stmt.returnType), null, null);
+            
+            method.visitCode(); // Start method body
+            
+            MethodBytecodeGenerator funcGenerator = new MethodBytecodeGenerator(classWriter, className, method, access, descriptor);
+            
+            // Add local variable indexes for each parameter
+            int lvidx = 0;
+            for (Pair<String, Type> parameter : stmt.parameters) {
+                funcGenerator.lvTable.put(parameter.getLeft(), lvidx);
+                lvidx += CodegenType.codegenType(parameter.getRight()).bytecodeType().slotSize(); // Increment by how many slots data type takes
+            }
+            
+            // Generate method bytecode
+            funcGenerator.generate(stmt.body);
+            
+            // Finish up
+            method.visitInsn(Opcodes.RETURN);
+            method.visitMaxs(0, 0);
+            method.visitEnd();
+            
+            return null;
+        }
+        
+        @Override
+        public Void visitVariableDeclarationTypedStmt(VariableDeclaration stmt) {
+            stmt.value.accept(this);
+            lvTable.put(stmt.identifier, lvs.newLocal(ASMUtil.tsTypeToAsmType(stmt.type)));
+            method.visitVarInsn(CodegenType.codegenType(stmt.type).bytecodeType().storeInsn(), lvTable.get(stmt.identifier));
+            return null;
+        }
+        
+        @Override
+        public Void visitReturnTypedStmt(Return stmt) {
+            stmt.value.accept(this);
+            method.visitInsn(CodegenType.codegenType(stmt.value.type).bytecodeType().returnInsn());
+            return null;
+        }
+        
+        @Override
+        public Void visitIfTypedStmt(If stmt) {
+            Label endIf = new Label();
+            conditionalStmt(stmt.condition, stmt.trueBody, endIf);
+            for(Pair<TypedExpr, Block> elseIfClause : stmt.elseIfClauses) {
+                conditionalStmt(elseIfClause.getLeft(), elseIfClause.getRight(), endIf);
+            }
+            stmt.elseBody.ifPresent(b -> b.accept(this));
+            label(endIf);
+            return null;
+        }
+        
+        @Override
+        public Void visitForTypedStmt(For stmt) {
+            Label loopStart = new Label();
+            Label loopBody = new Label();
+            Label loopEnd = new Label();
+            
+            stmt.initializer.accept(this);
+            jump(loopBody); // Skip over incrementer on first loop
+            
+            label(loopStart);
+            stmt.incrementer.accept(this);
+            label(loopBody);
+            loopStack.push(Pair.of(loopStart, loopEnd));
+            conditionalStmt(stmt.condition, stmt.body, loopStart);
+            loopStack.pop();
+            label(loopEnd);
+            return null;
+        }
+        
+        @Override
+        public Void visitWhileTypedStmt(While stmt) {
+            Label loopStart = new Label();
+            Label loopEnd = new Label();
+            
+            label(loopStart);
+            loopStack.push(Pair.of(loopStart, loopEnd));
+            conditionalStmt(stmt.condition, stmt.body, loopStart);
+            loopStack.pop();
+            label(loopEnd);
+            return null;
+        }
+        
+        @Override
+        public Void visitNoOpTypedStmt(NoOp stmt) {
+            return null;
+        }
+        
+        @Override
+        public Void visitBreakTypedStmt(Break stmt) {
+            jump(loopStack.getFirst().getRight());
+            return null;
+        }
+        
+        @Override
+        public Void visitContinueTypedStmt(Continue stmt) {
+            jump(loopStack.getFirst().getLeft());
+            return null;
+        }
+        
+        private boolean binaryOperandsSameType(Type type, Binary expr) {
+            return exprTypesEqual(type, expr.left, expr.right);
+        }
+        
+        private static boolean exprTypesEqual(Type type, TypedExpr... exprs) {
+            for(TypedExpr expr : exprs) {
+                if (expr.type != type) return false;
+            }
+            return true;
+        }
+        
+        /**
+         * Inverts a boolean on the stack
+         */
+        private void invertBool() {
+            Label invertToFalse = new Label();
+            Label finished = new Label();
+            jumpIf(OpcodeAlias.BOOL_TRUE, invertToFalse);
+            
+            pushFalse();
+            jump(finished);
+            
+            label(invertToFalse);
+            pushFalse();
+            
+            label(finished);
+        }
+        
+        private void pushBinaryOperands(Binary expr) {
+            expr.left.accept(this);
+            expr.right.accept(this);
+        }
+        
+        private void binaryInsn(Binary expr, int insn) {
+            pushBinaryOperands(expr);
+            method.visitInsn(insn);
+        }
+        
+        /**
+         * Pushes boolean on to the stack based on comparison result
+         * @param condition
+         */
+        private void pushComparisonBool(TypedExpr condition) {
+            Label trueFinished = new Label();
+            conditionalRunnable(condition, this::pushTrue, trueFinished);
+            pushFalse();
+            label(trueFinished);
+        }
+        
+        /**
+         * Executes a statement then jumps to the exit label if the condition is true, jumps over the statement if false
+         * @param condition
+         * @param stmt
+         * @param exit
+         */
+        private void conditionalStmt(TypedExpr condition, TypedStmt stmt, Label exit) {
+            conditionalRunnable(condition, () -> stmt.accept(this), exit);
+        }
+        
+        private void pushTrue() {
+            method.visitInsn(Opcodes.ICONST_1);
+        }
+        
+        private void pushFalse() {
+            method.visitInsn(Opcodes.ICONST_0);
+        }
+        
+        private void jumpIf(int opcode, Label label) {
+            method.visitJumpInsn(opcode, label);
+        }
+        
+        private void jump(Label label) {
+            method.visitJumpInsn(Opcodes.GOTO, label);
+        }
+        
+        private void label(Label label) {
+            method.visitLabel(label);
+        }
+        
+        private void conditionalRunnable(TypedExpr condition, Runnable trueBlock, Label trueFinished) {
+            Label exit = new Label(); // If the first conditional is false, jump over statement and don't execute it
+            if (condition instanceof Binary binaryCondition) {
+                switch(binaryCondition.operator) {
+                    case BOOLEAN_AND -> {
+                        // Operands assumed booleans
+                        binaryCondition.left.accept(this);
+                        jumpIf(OpcodeAlias.BOOL_FALSE, exit); // If left is false, short circuit, don't evaluate right
+                        binaryCondition.right.accept(this);
+                        jumpIf(OpcodeAlias.BOOL_FALSE, exit);
+                    }
+                    case BOOLEAN_OR -> {
+                        Label skipRight = new Label();
+                        // Operands assumed booleans
+                        binaryCondition.left.accept(this);
+                        jumpIf(OpcodeAlias.BOOL_TRUE, skipRight);
+                        binaryCondition.right.accept(this);
+                        jumpIf(OpcodeAlias.BOOL_FALSE, exit);
+                        label(skipRight);
+                    }
+                    case EQUALS -> {
+                        if (binaryOperandsSameType(Type.BOOLEAN, binaryCondition)) { // Operands assumed integers
+                            pushBinaryOperands(binaryCondition);
+                            jumpIf(OpcodeAlias.INTEGERS_NOT_EQUAL, exit);
+                            
+                        } else if (binaryOperandsSameType(Type.NUMBER, binaryCondition)) { // Operands assumed doubles
+                            binaryInsn(binaryCondition, Opcodes.DCMPG);
+                            jumpIf(OpcodeAlias.CMP_NOT_EQUALS, exit);
+                            
+                        } else if (binaryOperandsSameType(Type.STRING, binaryCondition)) {
+                            pushBinaryOperands(binaryCondition);
+                            method.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "equals", "(Ljava/lang/Object;)Z", false);
+                            jumpIf(OpcodeAlias.BOOL_FALSE, exit);
+                        } else throw new CompilerBugException();
+                    }
+                    case NOT_EQUALS -> {
+                        if (binaryOperandsSameType(Type.BOOLEAN, binaryCondition)) { // Operands assumed integers
+                            pushBinaryOperands(binaryCondition);
+                            jumpIf(OpcodeAlias.INTEGERS_EQUAL, exit);
+                            
+                        } else if (binaryOperandsSameType(Type.NUMBER, binaryCondition)) { // Operands assumed doubles
+                            binaryInsn(binaryCondition, Opcodes.DCMPG);
+                            jumpIf(OpcodeAlias.CMP_EQUALS, exit);
+                            
+                        } else if (binaryOperandsSameType(Type.STRING, binaryCondition)) { // Operands assumed references
+                            pushBinaryOperands(binaryCondition);
+                            method.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/String", "equals", "(Ljava/lang/Object;)Z", false);
+                            invertBool();
+                            jumpIf(OpcodeAlias.CMP_EQUALS, exit);
+                        } else throw new CompilerBugException();
+                    }
+                    case GREATER, GREATER_EQUALS, LESS, LESS_EQUALS -> {
+                        // Left and right assumed double
+                        binaryInsn(binaryCondition, switch(binaryCondition.operator) {
+                            case GREATER, GREATER_EQUALS -> Opcodes.DCMPL;
+                            case LESS, LESS_EQUALS -> Opcodes.DCMPG;
+                            default -> throw new IllegalStateException();
+                        });
+                        
+                        jumpIf(switch(binaryCondition.operator) {
+                            case GREATER -> OpcodeAlias.CMP_LESS_EQUALS;
+                            case GREATER_EQUALS -> OpcodeAlias.CMP_LESS_THAN;
+                            case LESS -> OpcodeAlias.CMP_GREATER_EQUALS;
+                            case LESS_EQUALS -> OpcodeAlias.CMP_GREATER_THAN;
+                            default -> throw new IllegalStateException();
+                        }, exit);
+                    }
+                    default -> throw new CompilerBugException();
+                }
+            } else {
+                // Assume condition returns bool
+                condition.accept(this);
+                jumpIf(OpcodeAlias.BOOL_FALSE, exit);
+            }
+            trueBlock.run();
+            jump(trueFinished); // Jump to end of statement after execution
+            label(exit);
+        }
+        
+        private String getFunctionDescriptor(List<Type> parameters, Type returnType) {
+            StringBuilder sb = new StringBuilder().append("(");
+            parameters.stream().map(parameter -> CodegenType.codegenType(parameter).getDescriptor()).forEach(sb::append);
+            sb.append(")");
+            sb.append(CodegenType.codegenType(returnType).getDescriptor());
+            return sb.toString();
+        }
+    }
+    
+    private static class MethodExtractor extends ClassVisitor {
+        
+        private final String methodName;
+        private String methodDescription;
+        
+        protected MethodExtractor(String methodName) {
+            super(Opcodes.ASM9);
+            this.methodName = methodName;
+        }
+        
+        @Override
+        public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
+            if (name.equals(methodName))
+                methodDescription = descriptor;
+            return super.visitMethod(access, name, descriptor, signature, exceptions);
+        }
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/CompilationException.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.exception;
+
+import java.io.Serial;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class CompilationException extends Exception {
+    @Serial
+    private static final long serialVersionUID = 6744390543046766386L;
+    private final SourcePosition position;
+    
+    public CompilationException(String message, SourcePosition position) {
+        super(message);
+        this.position = position;
+    }
+    
+    @Override
+    public String getMessage() {
+        return "Error at " + position + ": " + super.getMessage();
+    }
+    
+    public SourcePosition getPosition() {
+        return position;
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/CompilerBugException.java

@@ -0,0 +1,5 @@
+package com.dfsek.terra.addons.terrascript.v2.exception;
+
+public class CompilerBugException extends RuntimeException {
+    // TODO - Add message constructor
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/lexer/EOFException.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.exception.lexer;
+
+import java.io.Serial;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class EOFException extends TokenizerException {
+    
+    @Serial
+    private static final long serialVersionUID = 3980047409902809440L;
+    
+    public EOFException(String message, SourcePosition position) {
+        super(message, position);
+    }
+    
+    public EOFException(String message, SourcePosition position, Throwable cause) {
+        super(message, position, cause);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/lexer/FormatException.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.exception.lexer;
+
+import java.io.Serial;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class FormatException extends TokenizerException {
+    
+    @Serial
+    private static final long serialVersionUID = -791308012940744455L;
+    
+    public FormatException(String message, SourcePosition position) {
+        super(message, position);
+    }
+    
+    public FormatException(String message, SourcePosition position, Throwable cause) {
+        super(message, position, cause);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/lexer/TokenizerException.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.exception.lexer;
+
+import java.io.Serial;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+import com.dfsek.terra.addons.terrascript.v2.parser.ParseException;
+
+
+public abstract class TokenizerException extends ParseException {
+    
+    @Serial
+    private static final long serialVersionUID = 2792384010083575420L;
+    
+    public TokenizerException(String message, SourcePosition position) {
+        super(message, position);
+    }
+    
+    public TokenizerException(String message, SourcePosition position, Throwable cause) {
+        super(message, position, cause);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/semanticanalysis/IdentifierAlreadyDeclaredException.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilationException;
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class IdentifierAlreadyDeclaredException extends CompilationException {
+    public IdentifierAlreadyDeclaredException(String message, SourcePosition position) {
+        super(message, position);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/semanticanalysis/InvalidFunctionDeclarationException.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilationException;
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class InvalidFunctionDeclarationException extends CompilationException {
+    public InvalidFunctionDeclarationException(String message, SourcePosition position) {
+        super(message, position);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/semanticanalysis/InvalidTypeException.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilationException;
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class InvalidTypeException extends CompilationException {
+    public InvalidTypeException(String message, SourcePosition position) {
+        super(message, position);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/exception/semanticanalysis/UndefinedReferenceException.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.CompilationException;
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class UndefinedReferenceException extends CompilationException {
+    public UndefinedReferenceException(String message, SourcePosition position) {
+        super(message, position);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/lexer/Char.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.lexer;
+
+import java.util.Objects;
+
+
+public class Char {
+    private final char character;
+    private final SourcePosition position;
+    
+    
+    public Char(char character, SourcePosition position) {
+        this.character = character;
+        this.position = position;
+    }
+    
+    public boolean is(char... tests) {
+        for(char test : tests) {
+            if(test == character && test != '\0') {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+    @Override
+    public String toString() {
+        return Character.toString(character);
+    }
+    
+    @Override
+    public boolean equals(Object o) {
+        if(this == o) return true;
+        if(o == null || getClass() != o.getClass()) return false;
+        Char other = (Char) o;
+        return character == other.character && Objects.equals(position, other.position);
+    }
+    
+    @Override
+    public int hashCode() {
+        return Objects.hash(character, position);
+    }
+    
+    public char getCharacter() {
+        return character;
+    }
+    
+    public boolean isWhitespace() {
+        return Character.isWhitespace(character);
+    }
+    
+    public boolean isNewLine() {
+        return character == '\n';
+    }
+    
+    public boolean isDigit() {
+        return Character.isDigit(character);
+    }
+    
+    public boolean isEOF() {
+        return character == '\0';
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/lexer/Lexer.java

@@ -0,0 +1,257 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.lexer;
+
+import com.dfsek.terra.addons.terrascript.v2.parser.ParseException;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.lexer.EOFException;
+import com.dfsek.terra.addons.terrascript.v2.exception.lexer.FormatException;
+import com.dfsek.terra.addons.terrascript.v2.exception.lexer.TokenizerException;
+
+import com.google.common.collect.Sets;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Set;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token.TokenType;
+
+
+public class Lexer {
+    public static final Set<Character> syntaxSignificant = Sets.newHashSet(':', ';', '(', ')', '"', ',', '\\', '=', '{', '}', '+', '-', '*',
+                                                                           '/',
+                                                                           '>', '<', '!'); // Reserved chars
+    private final LookaheadStream reader;
+    private Token current;
+    
+    public Lexer(String data) {
+        reader = new LookaheadStream(data + '\0');
+        current = tokenize();
+    }
+    
+    public List<Token> analyze() {
+        List<Token> tokens = new ArrayList<>();
+        while(hasNext()) {
+            tokens.add(consumeUnchecked());
+        }
+        tokens.add(current()); // Add EOF token
+        return tokens;
+    }
+    
+    /**
+     * Get the first token.
+     *
+     * @return First token
+     *
+     * @throws ParseException If token does not exist
+     */
+    public Token current() {
+        return current;
+    }
+    
+    /**
+     * Consume (get and remove) the first token.
+     *
+     * @return First token
+     *
+     * @throws ParseException If token does not exist
+     */
+    public Token consume(String wrongTypeMessage, TokenType expected, TokenType... more) {
+        if(!current.isType(expected) && Arrays.stream(more).noneMatch(t -> t == current.type())) throw new ParseException(wrongTypeMessage,
+                                                                                                                          current.position());
+        return consumeUnchecked();
+    }
+    
+    public Token consumeUnchecked() {
+        if(current.type() == TokenType.END_OF_FILE) return current;
+        Token temp = current;
+        current = tokenize();
+        return temp;
+    }
+    
+    /**
+     * Whether this {@code Tokenizer} contains additional tokens.
+     *
+     * @return {@code true} if more tokens are present, otherwise {@code false}
+     */
+    public boolean hasNext() {
+        return current.type() != TokenType.END_OF_FILE;
+    }
+    
+    private Token tokenize() throws TokenizerException {
+        consumeWhitespace();
+        SourcePosition position = reader.getPosition();
+        
+        // Skip line if comment
+        while(reader.matchesString("//", true)) skipLine();
+        
+        // Skip multi line comment
+        if(reader.matchesString("/*", true)) skipTo("*/");
+        
+        // Reached end of file
+        if(reader.current().isEOF()) return new Token(reader.consume().toString(), TokenType.END_OF_FILE, position);
+        
+        // Check if operator token
+        if(reader.matchesString("==", true))
+            return new Token("==", TokenType.EQUALS_EQUALS, position);
+        if(reader.matchesString("!=", true))
+            return new Token("!=", TokenType.BANG_EQUALS, position);
+        if(reader.matchesString(">=", true))
+            return new Token(">=", TokenType.GREATER_EQUAL, position);
+        if(reader.matchesString("<=", true))
+            return new Token("<=", TokenType.LESS_EQUALS, position);
+        if(reader.matchesString(">", true))
+            return new Token(">", TokenType.GREATER, position);
+        if(reader.matchesString("<", true))
+            return new Token("<", TokenType.LESS, position);
+        
+        // Check if logical operator
+        if(reader.matchesString("||", true))
+            return new Token("||", TokenType.BOOLEAN_OR, position);
+        if(reader.matchesString("&&", true))
+            return new Token("&&", TokenType.BOOLEAN_AND, position);
+        
+        // Check if number
+        if(isNumberStart()) {
+            StringBuilder num = new StringBuilder();
+            while(!reader.current().isEOF() && isNumberLike()) {
+                num.append(reader.consume().getCharacter());
+            }
+            return new Token(num.toString(), TokenType.NUMBER, position);
+        }
+        
+        // Check if string literal
+        if(reader.current().is('"')) {
+            reader.consume(); // Consume first quote
+            StringBuilder string = new StringBuilder();
+            boolean ignoreNext = false;
+            while((!reader.current().is('"')) || ignoreNext) {
+                if(reader.current().is('\\') && !ignoreNext) {
+                    ignoreNext = true;
+                    reader.consume();
+                    continue;
+                } else ignoreNext = false;
+                if(reader.current().isEOF())
+                    throw new FormatException("No end of string literal found. ", position);
+                string.append(reader.consume());
+            }
+            reader.consume(); // Consume last quote
+            
+            return new Token(string.toString(), TokenType.STRING, position);
+        }
+        
+        if(reader.current().is('('))
+            return new Token(reader.consume().toString(), TokenType.OPEN_PAREN, position);
+        if(reader.current().is(')'))
+            return new Token(reader.consume().toString(), TokenType.CLOSE_PAREN, position);
+        if(reader.current().is(':'))
+            return new Token(reader.consume().toString(), TokenType.COLON, position);
+        if(reader.current().is(';'))
+            return new Token(reader.consume().toString(), TokenType.STATEMENT_END, position);
+        if(reader.current().is(','))
+            return new Token(reader.consume().toString(), TokenType.SEPARATOR, position);
+        
+        if(reader.current().is('{')) return new Token(reader.consume().toString(), TokenType.BLOCK_BEGIN, position);
+        if(reader.current().is('}')) return new Token(reader.consume().toString(), TokenType.BLOCK_END, position);
+        
+        if(reader.current().is('='))
+            return new Token(reader.consume().toString(), TokenType.ASSIGNMENT, position);
+        if(reader.current().is('+'))
+            return new Token(reader.consume().toString(), TokenType.PLUS, position);
+        if(reader.current().is('-'))
+            return new Token(reader.consume().toString(), TokenType.MINUS,
+                             position);
+        if(reader.current().is('*'))
+            return new Token(reader.consume().toString(), TokenType.STAR,
+                             position);
+        if(reader.current().is('/'))
+            return new Token(reader.consume().toString(), TokenType.FORWARD_SLASH, position);
+        if(reader.current().is('%'))
+            return new Token(reader.consume().toString(), TokenType.MODULO_OPERATOR, position);
+        if(reader.current().is('!'))
+            return new Token(reader.consume().toString(), TokenType.BANG, position);
+        
+        // Read word
+        StringBuilder token = new StringBuilder();
+        while(!reader.current().isEOF() && !isSyntaxSignificant(reader.current().getCharacter())) {
+            Char c = reader.consume();
+            if(c.isWhitespace()) break;
+            token.append(c.getCharacter());
+        }
+        String tokenString = token.toString();
+        
+        // Check if word is a keyword
+        if(tokenString.equals("true"))
+            return new Token(tokenString, TokenType.BOOLEAN, position);
+        if(tokenString.equals("false"))
+            return new Token(tokenString, TokenType.BOOLEAN, position);
+        
+        if(tokenString.equals("var"))
+            return new Token(tokenString, TokenType.VARIABLE, position);
+        
+        if(tokenString.equals("fun"))
+            return new Token(tokenString, TokenType.FUNCTION, position);
+        
+        if(tokenString.equals("if"))
+            return new Token(tokenString, TokenType.IF_STATEMENT, position);
+        if(tokenString.equals("else"))
+            return new Token(tokenString, TokenType.ELSE, position);
+        if(tokenString.equals("while"))
+            return new Token(tokenString, TokenType.WHILE_LOOP, position);
+        if(tokenString.equals("for"))
+            return new Token(tokenString, TokenType.FOR_LOOP, position);
+        
+        if(tokenString.equals("return"))
+            return new Token(tokenString, TokenType.RETURN, position);
+        if(tokenString.equals("continue"))
+            return new Token(tokenString, TokenType.CONTINUE, position);
+        if(tokenString.equals("break"))
+            return new Token(tokenString, TokenType.BREAK, position);
+        if(tokenString.equals("fail"))
+            return new Token(tokenString, TokenType.FAIL, position);
+        
+        // If not keyword, assume it is an identifier
+        return new Token(tokenString, TokenType.IDENTIFIER, position);
+    }
+    
+    private void skipLine() {
+        while(!reader.current().isEOF() && !reader.current().isNewLine()) reader.consume();
+        consumeWhitespace();
+    }
+    
+    private void consumeWhitespace() {
+        while(!reader.current().isEOF() && reader.current().isWhitespace()) reader.consume(); // Consume whitespace.
+    }
+    
+    private void skipTo(String s) throws EOFException {
+        SourcePosition begin = reader.getPosition();
+        while(!reader.current().isEOF()) {
+            if(reader.matchesString(s, true)) {
+                consumeWhitespace();
+                return;
+            }
+            reader.consume();
+        }
+        throw new EOFException("Reached end of file without matching '" + s + "'", begin);
+    }
+    
+    private boolean isNumberLike() {
+        return reader.current().isDigit()
+               || reader.current().is('_', '.', 'E');
+    }
+    
+    private boolean isNumberStart() {
+        return reader.current().isDigit()
+               || reader.current().is('.') && reader.peek().isDigit();
+    }
+    
+    public boolean isSyntaxSignificant(char c) {
+        return syntaxSignificant.contains(c);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/lexer/LookaheadStream.java

@@ -0,0 +1,84 @@
+package com.dfsek.terra.addons.terrascript.v2.lexer;
+
+
+public class LookaheadStream {
+    
+    private final String source;
+    
+    private int index;
+    
+    private SourcePosition position = new SourcePosition(1, 1);
+    
+    public LookaheadStream(String source) {
+        this.source = source;
+    }
+    
+    /**
+     * Get the current character without consuming it.
+     *
+     * @return current character
+     */
+    public Char current() {
+        return new Char(source.charAt(index), position);
+    }
+    
+    /**
+     * Consume and return one character.
+     *
+     * @return Character that was consumed.
+     */
+    public Char consume() {
+        Char consumed = current();
+        incrementIndex(1);
+        return consumed;
+    }
+    
+    /**
+     * @return The next character in sequence.
+     */
+    public Char peek() {
+        int index = this.index + 1;
+        if(index + 1 >= source.length()) return null;
+        return new Char(source.charAt(index), getPositionAfter(1));
+    }
+    
+    /**
+     * Determines if the contained sequence of characters matches the string
+     *
+     * @param check            Input string to check against
+     * @param consumeIfMatched Whether to consume the string if there is a match
+     *
+     * @return If the string matches
+     */
+    public boolean matchesString(String check, boolean consumeIfMatched) {
+        boolean matches = check.equals(source.substring(index, Math.min(index + check.length(), source.length())));
+        if(matches && consumeIfMatched) incrementIndex(check.length());
+        return matches;
+    }
+    
+    /**
+     * @return Current position within the source file
+     */
+    public SourcePosition getPosition() {
+        return position;
+    }
+    
+    private void incrementIndex(int amount) {
+        position = getPositionAfter(amount);
+        index = Math.min(index + amount, source.length() - 1);
+    }
+    
+    private SourcePosition getPositionAfter(int chars) {
+        if(chars < 0) throw new IllegalArgumentException("Negative values are not allowed");
+        int line = position.line();
+        int column = position.column();
+        for(int i = index; i < Math.min(index + chars, source.length() - 1); i++) {
+            if(source.charAt(i) == '\n') {
+                line++;
+                column = 0;
+            }
+            column++;
+        }
+        return new SourcePosition(line, column);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/lexer/SourcePosition.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.lexer;
+
+import java.util.Objects;
+
+
+public record SourcePosition(int line, int column) {
+    
+    @Override
+    public String toString() {
+        return "line " + line + ", column " + column;
+    }
+    
+    @Override
+    public boolean equals(Object o) {
+        if(this == o) return true;
+        if(o == null || getClass() != o.getClass()) return false;
+        SourcePosition that = (SourcePosition) o;
+        return line == that.line && column == that.column;
+    }
+    
+    @Override
+    public int hashCode() {
+        return Objects.hash(line, column);
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/lexer/Token.java

@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.lexer;
+
+import java.util.Objects;
+
+
+public class Token {
+    private final String lexeme;
+    private final TokenType type;
+    private final SourcePosition start;
+    
+    public Token(String lexeme, TokenType type, SourcePosition start) {
+        this.lexeme = type == TokenType.END_OF_FILE ? "END OF FILE" : lexeme;
+        this.type = type;
+        this.start = start;
+    }
+    
+    @Override
+    public boolean equals(Object o) {
+        if(this == o) return true;
+        if(o == null || getClass() != o.getClass()) return false;
+        Token token = (Token) o;
+        return Objects.equals(lexeme, token.lexeme) && type == token.type && Objects.equals(start, token.start);
+    }
+    
+    @Override
+    public int hashCode() {
+        return Objects.hash(lexeme, type, start);
+    }
+    
+    @Override
+    public String toString() {
+        return type + ": '" + lexeme + "'";
+    }
+    
+    public TokenType type() {
+        return type;
+    }
+    
+    public String lexeme() {
+        return lexeme;
+    }
+    
+    public SourcePosition position() {
+        return start;
+    }
+    
+    public boolean isType(TokenType... types) {
+        for(TokenType t : types) if(t == type) return true;
+        return false;
+    }
+    
+    public enum TokenType {
+        /**
+         * Function identifier or language keyword
+         */
+        IDENTIFIER,
+        
+        /**
+         * Numeric literal
+         */
+        NUMBER,
+        /**
+         * String literal
+         */
+        STRING,
+        /**
+         * Boolean literal
+         */
+        BOOLEAN,
+        /**
+         * Beginning of group
+         */
+        OPEN_PAREN,
+        /**
+         * Ending of group
+         */
+        CLOSE_PAREN,
+        /**
+         * End of statement
+         */
+        STATEMENT_END,
+        /**
+         * Argument separator
+         */
+        SEPARATOR,
+        /**
+         * Beginning of code block
+         */
+        BLOCK_BEGIN,
+        /**
+         * End of code block
+         */
+        BLOCK_END,
+        /**
+         * assignment operator
+         */
+        ASSIGNMENT,
+        /**
+         * Boolean equals operator
+         */
+        EQUALS_EQUALS,
+        /**
+         * Boolean not equals operator
+         */
+        BANG_EQUALS,
+        /**
+         * Boolean greater than operator
+         */
+        GREATER,
+        /**
+         * Boolean less than operator
+         */
+        LESS,
+        /**
+         * Boolean greater than or equal to operator
+         */
+        GREATER_EQUAL,
+        /**
+         * Boolean less than or equal to operator
+         */
+        LESS_EQUALS,
+        /**
+         * Addition/concatenation operator
+         */
+        PLUS,
+        /**
+         * Subtraction operator
+         */
+        MINUS,
+        /**
+         * Multiplication operator
+         */
+        STAR,
+        /**
+         * Division operator
+         */
+        FORWARD_SLASH,
+        /**
+         * Modulo operator.
+         */
+        MODULO_OPERATOR,
+        /**
+         * Boolean not operator
+         */
+        BANG,
+        /**
+         * Boolean or
+         */
+        BOOLEAN_OR,
+        /**
+         * Boolean and
+         */
+        BOOLEAN_AND,
+        /**
+         * Variable declaration
+         */
+        VARIABLE,
+        /**
+         * Function declaration
+         */
+        FUNCTION,
+        COLON,
+        /**
+         * If statement declaration
+         */
+        IF_STATEMENT,
+        /**
+         * While loop declaration
+         */
+        WHILE_LOOP,
+        /**
+         * Return statement
+         */
+        RETURN,
+        /**
+         * Continue statement
+         */
+        CONTINUE,
+        /**
+         * Break statement
+         */
+        BREAK,
+        /**
+         * Fail statement. Like return keyword, but specifies that generation has failed.
+         */
+        FAIL,
+        /**
+         * For loop initializer token
+         */
+        FOR_LOOP,
+        /**
+         * Else keyword
+         */
+        ELSE,
+        /**
+         * End of file
+         */
+        END_OF_FILE
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/parser/BinaryOperator.java

@@ -0,0 +1,25 @@
+package com.dfsek.terra.addons.terrascript.v2.parser;
+
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token;
+
+
+public enum BinaryOperator {
+    BOOLEAN_OR(Token.TokenType.BOOLEAN_OR),
+    BOOLEAN_AND(Token.TokenType.BOOLEAN_AND),
+    EQUALS(Token.TokenType.EQUALS_EQUALS),
+    NOT_EQUALS(Token.TokenType.BANG_EQUALS),
+    GREATER(Token.TokenType.GREATER),
+    GREATER_EQUALS(Token.TokenType.GREATER_EQUAL),
+    LESS(Token.TokenType.LESS),
+    LESS_EQUALS(Token.TokenType.LESS_EQUALS),
+    ADD(Token.TokenType.PLUS),
+    SUBTRACT(Token.TokenType.MINUS),
+    MULTIPLY(Token.TokenType.STAR),
+    DIVIDE(Token.TokenType.FORWARD_SLASH),
+    MODULO(Token.TokenType.MODULO_OPERATOR);
+    
+    public final Token.TokenType tokenType;
+    
+    BinaryOperator(Token.TokenType tokenType) { this.tokenType = tokenType; }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/parser/ParseException.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package com.dfsek.terra.addons.terrascript.v2.parser;
+
+import java.io.Serial;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+
+public class ParseException extends RuntimeException {
+    @Serial
+    private static final long serialVersionUID = 6744390543046766386L;
+    private final SourcePosition position;
+    
+    public ParseException(String message, SourcePosition position) {
+        super(message);
+        this.position = position;
+    }
+    
+    public ParseException(String message, SourcePosition position, Throwable cause) {
+        super(message, cause);
+        this.position = position;
+    }
+    
+    @Override
+    public String getMessage() {
+        return "Error at " + position + ": " + super.getMessage();
+    }
+    
+    public SourcePosition getPosition() {
+        return position;
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/parser/Parser.java

@@ -0,0 +1,379 @@
+package com.dfsek.terra.addons.terrascript.v2.parser;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Supplier;
+
+import com.dfsek.terra.addons.terrascript.v2.Type;
+import com.dfsek.terra.addons.terrascript.v2.Type.TypeException;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Variable;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Block;
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token.TokenType;
+import com.dfsek.terra.api.util.generic.pair.Pair;
+
+
+/**
+ * TerraScript recursive descent parser
+ */
+public class Parser {
+    
+    private final List<Token> tokens;
+    
+    private int index = 0;
+    
+    private Parser(List<Token> tokens) {
+        if(tokens.stream().noneMatch(t -> t.isType(TokenType.END_OF_FILE)))
+            throw new IllegalArgumentException("Token list must contain at least one token of type " + TokenType.END_OF_FILE);
+        this.tokens = tokens;
+    }
+    
+    public static Block parse(List<Token> tokens) {
+        return new Parser(tokens).parseTokens();
+    }
+    
+    private Block parseTokens() {
+        List<Stmt> statements = new ArrayList<>();
+        while(hasNext()) {
+            statements.add(statement());
+        }
+        if(hasNext()) throw new ParseException("Tokens were remaining after parsing", current().position());
+        return new Stmt.Block(statements, new SourcePosition(0, 0));
+    }
+    
+    private Token current() {
+        return tokens.get(index);
+    }
+    
+    private boolean hasNext() {
+        return !current().isType(TokenType.END_OF_FILE);
+    }
+    
+    private Token consume(String wrongTypeMessage, TokenType expected, TokenType... more) {
+        if(!current().isType(expected) && Arrays.stream(more).noneMatch(t -> t == current().type())) throw new ParseException(
+                wrongTypeMessage, current().position());
+        return consumeUnchecked();
+    }
+    
+    public Token consumeUnchecked() {
+        if(!hasNext()) return current();
+        Token temp = current();
+        index++;
+        return temp;
+    }
+    
+    private void consumeStatementEnd(String after) {
+        consume("Expected ';' after " + after + ", found '" + current().lexeme() + "'", TokenType.STATEMENT_END);
+    }
+    
+    private Stmt statement() {
+        return switch(current().type()) {
+            case BLOCK_BEGIN -> block();
+            case FUNCTION -> functionDeclaration();
+            case VARIABLE -> variableDeclaration();
+            case RETURN -> returnStmt();
+            case IF_STATEMENT -> ifStmt();
+            case FOR_LOOP -> forLoop();
+            case WHILE_LOOP -> whileLoop();
+            case BREAK -> breakStmt();
+            case CONTINUE -> continueStmt();
+            case STATEMENT_END -> new Stmt.NoOp(consumeUnchecked().position());
+            default -> expressionStatement();
+        };
+    }
+    
+    private Stmt functionDeclaration() {
+        SourcePosition position = consume("Expected 'fun' keyword at start of function declaration", TokenType.FUNCTION).position();
+        String id = consume("Expected identifier after 'fun' keyword for function declaration", TokenType.IDENTIFIER).lexeme();
+        consume("Expected '(' after function identifier '" + id + "'", TokenType.OPEN_PAREN);
+        
+        // Parse parameters
+        List<Pair<String, Type>> params = new ArrayList<>();
+        while(!current().isType(TokenType.CLOSE_PAREN)) {
+            Token paramToken = consume("Expected parameter name or ')', found '" + current().lexeme() + "'", TokenType.IDENTIFIER);
+            String paramId = paramToken.lexeme();
+            if(params.stream().anyMatch(p -> Objects.equals(p.getLeft(), paramId)))
+                throw new ParseException("Parameter '" + paramId + "' has already been declared in function '" + id + "'",
+                                         paramToken.position());
+            
+            consume("Expected type declaration after parameter name. Example: '" + paramId + ": <type>'", TokenType.COLON);
+            Type paramType = typeExpr();
+            
+            params.add(Pair.of(paramId, paramType));
+            
+            if(current().isType(TokenType.CLOSE_PAREN)) break;
+            consume("Expected ',' or ')' after parameter declaration '" + paramId + "' in function '" + id + "'", TokenType.SEPARATOR);
+        }
+        
+        Type funcReturn = Type.VOID;
+        
+        consume("Expected ')' after " + (params.size() == 0 ? "')'" : "parameters") + " in declaration of function '" + id + "'",
+                TokenType.CLOSE_PAREN);
+        if(current().isType(TokenType.COLON)) {
+            consumeUnchecked();
+            funcReturn = typeExpr();
+        }
+        
+        Stmt.Block body = blockOrSingleStatement();
+        
+        return new Stmt.FunctionDeclaration(id, params, funcReturn, body, position);
+    }
+    
+    private Stmt.VariableDeclaration variableDeclaration() {
+        SourcePosition position = consume("Expected 'var' keyword at start of variable declaration", TokenType.VARIABLE).position();
+        String id = consume("Expected variable name after type for variable declaration", TokenType.IDENTIFIER).lexeme();
+        consume("Expected ':' after variable name", TokenType.COLON);
+        Type type = typeExpr();
+        consume("Expected '=' following variable type declaration", TokenType.ASSIGNMENT);
+        Expr expr = expression();
+        consumeStatementEnd("variable declaration");
+        
+        return new Stmt.VariableDeclaration(type, id, expr, position);
+    }
+    
+    private Type typeExpr() {
+        Token typeToken = consume("Expected " + TokenType.IDENTIFIER + " specified as variable type", TokenType.IDENTIFIER);
+        try {
+            return Type.fromString(typeToken.lexeme());
+        } catch(TypeException e) {
+            throw new ParseException("Failed to parse type expression", typeToken.position());
+        }
+    }
+    
+    private Stmt.Return returnStmt() {
+        SourcePosition position = consume("Expected 'return' keyword, found '" + current().lexeme() + "'", TokenType.RETURN).position();
+        Expr value = new Expr.Void(position);
+        if(!current().isType(TokenType.STATEMENT_END))
+            value = expression();
+        consumeStatementEnd("return statement");
+        return new Stmt.Return(value, position);
+    }
+    
+    private Stmt.If ifStmt() {
+        // Parse main if clause
+        SourcePosition position = consume("Expected 'if' keyword at beginning of if statement", TokenType.IF_STATEMENT).position();
+        consume("Expected '(' after 'if' keyword", TokenType.OPEN_PAREN);
+        Expr condition = expression();
+        consume("Expected ')' after if statement condition", TokenType.CLOSE_PAREN);
+        Stmt.Block trueBody = blockOrSingleStatement();
+        
+        // Parse any else clauses
+        Stmt.Block elseBody = null;
+        List<Pair<Expr, Stmt.Block>> elseIfClauses = new ArrayList<>();
+        while(current().isType(TokenType.ELSE)) {
+            consumeUnchecked(); // Consume else
+            
+            if(!current().isType(TokenType.IF_STATEMENT)) {
+                elseBody = blockOrSingleStatement();
+                break; // Else clause should be last in if statement
+            }
+            
+            consumeUnchecked(); // Consume if
+            consume("Expected '(' after 'else if', e.g. 'if else (<condition>) ...'", TokenType.OPEN_PAREN);
+            Expr elseIfCondition = expression();
+            consume("Expected ')' after 'else if' clause, e.g. 'else if (<condition>) ...'", TokenType.CLOSE_PAREN);
+            Stmt.Block elseIfBody = blockOrSingleStatement();
+            elseIfClauses.add(Pair.of(elseIfCondition, elseIfBody));
+        }
+        
+        return new Stmt.If(condition, trueBody, elseIfClauses, Optional.ofNullable(elseBody), position);
+    }
+    
+    private Stmt.For forLoop() {
+        SourcePosition position = consume("Expected 'for' keyword at beginning of for loop", TokenType.FOR_LOOP).position();
+        consume("Expected '(' after 'for' keyword", TokenType.OPEN_PAREN);
+        Stmt initializer = statement();
+        Expr condition;
+        if(current().isType(TokenType.STATEMENT_END)) {
+            condition = new Expr.Literal(true, Type.BOOLEAN,
+                                         current().position()); // If no condition is provided, set condition = true
+            consumeUnchecked();
+        } else {
+            condition = expression();
+            consumeStatementEnd("loop condition");
+        }
+        Expr incrementer;
+        if(current().isType(TokenType.CLOSE_PAREN)) {
+            incrementer = null;
+            consumeUnchecked();
+        } else {
+            incrementer = expression();
+            consume("Expected ')' after for loop incrementer", TokenType.CLOSE_PAREN);
+        }
+        Stmt.Block body = blockOrSingleStatement();
+        return new Stmt.For(initializer, condition, incrementer, body, position);
+    }
+    
+    private Stmt.While whileLoop() {
+        SourcePosition position = consume("Expected 'for' keyword at beginning of while loop", TokenType.WHILE_LOOP).position();
+        consume("Expected '(' after 'while' keyword", TokenType.OPEN_PAREN);
+        Expr condition = expression();
+        consume("Expected ')' after while loop condition", TokenType.CLOSE_PAREN);
+        Stmt.Block body = blockOrSingleStatement();
+        return new Stmt.While(condition, body, position);
+    }
+    
+    private Stmt.Break breakStmt() {
+        SourcePosition position = consume("Expected 'break' keyword for break statement", TokenType.BREAK).position();
+        consumeStatementEnd("'break' keyword");
+        return new Stmt.Break(position);
+    }
+    
+    private Stmt.Continue continueStmt() {
+        SourcePosition position = consume("Expected 'continue' keyword for continue statement", TokenType.CONTINUE).position();
+        consumeStatementEnd("'continue' keyword");
+        return new Stmt.Continue(position);
+    }
+    
+    private Stmt.Block blockOrSingleStatement() {
+        if(!current().isType(TokenType.BLOCK_BEGIN)) return new Stmt.Block(List.of(statement()), current().position());
+        return block();
+    }
+    
+    private Stmt.Block block() {
+        SourcePosition position = consume("Expected '{' at start of block", TokenType.BLOCK_BEGIN).position();
+        List<Stmt> statements = new ArrayList<>();
+        while(!current().isType(TokenType.BLOCK_END)) {
+            statements.add(statement());
+        }
+        consume("Expected '}' at end of block", TokenType.BLOCK_END);
+        return new Stmt.Block(statements, position);
+    }
+    
+    private Stmt expressionStatement() {
+        Expr expression = expression();
+        consumeStatementEnd("expression statement");
+        return new Stmt.Expression(expression, expression.position);
+    }
+    
+    private Expr expression() {
+        return assignment();
+    }
+    
+    private Expr leftAssociativeBinaryExpression(Supplier<Expr> higherPrecedence, BinaryOperator... operators) {
+        Expr expr = higherPrecedence.get();
+        loop:
+        while(true) {
+            for(BinaryOperator operator : operators) {
+                if(current().isType(operator.tokenType)) {
+                    SourcePosition position = consumeUnchecked().position(); // Consume operator token
+                    expr = new Expr.Binary(expr, operator, higherPrecedence.get(), position);
+                    continue loop;
+                }
+            }
+            break; // Break if not any operator
+        }
+        return expr;
+    }
+    
+    private Expr rightAssociativeBinaryExpression(Supplier<Expr> higherPrecedence, BinaryOperator... operators) {
+        Expr expr = higherPrecedence.get();
+        for(BinaryOperator operator : operators) {
+            if(current().isType(operator.tokenType)) {
+                SourcePosition position = consumeUnchecked().position(); // Consume operator token
+                return new Expr.Binary(expr, operator, rightAssociativeBinaryExpression(higherPrecedence, operators), position);
+            }
+        }
+        return expr;
+    }
+    
+    private Expr assignment() {
+        Expr expr = logicOr();
+        if(current().isType(TokenType.ASSIGNMENT)) {
+            SourcePosition position = consumeUnchecked().position(); // Consume operator token
+            if(!(expr instanceof Variable variable)) throw new ParseException("Invalid assignment target", position);
+            return new Expr.Assignment(variable, assignment(), position);
+        }
+        return expr;
+    }
+    
+    private Expr logicOr() {
+        return leftAssociativeBinaryExpression(this::logicAnd, BinaryOperator.BOOLEAN_OR);
+    }
+    
+    private Expr logicAnd() {
+        return leftAssociativeBinaryExpression(this::equality, BinaryOperator.BOOLEAN_AND);
+    }
+    
+    private Expr equality() {
+        return leftAssociativeBinaryExpression(this::comparison, BinaryOperator.EQUALS, BinaryOperator.NOT_EQUALS);
+    }
+    
+    private Expr comparison() {
+        return leftAssociativeBinaryExpression(this::term, BinaryOperator.GREATER, BinaryOperator.GREATER_EQUALS, BinaryOperator.LESS,
+                                               BinaryOperator.LESS_EQUALS);
+    }
+    
+    private Expr term() {
+        return leftAssociativeBinaryExpression(this::factor, BinaryOperator.ADD, BinaryOperator.SUBTRACT);
+    }
+    
+    private Expr factor() {
+        return leftAssociativeBinaryExpression(this::unary, BinaryOperator.MULTIPLY, BinaryOperator.DIVIDE, BinaryOperator.MODULO);
+    }
+    
+    private Expr unary() {
+        UnaryOperator[] operators = { UnaryOperator.NOT, UnaryOperator.NEGATE };
+        for(UnaryOperator operator : operators) {
+            if(current().isType(operator.tokenType)) {
+                SourcePosition position = consumeUnchecked().position();
+                return new Expr.Unary(operator, unary(), position);
+            }
+        }
+        return primary();
+    }
+    
+    private Expr primary() {
+        Token token = consumeUnchecked();
+        SourcePosition position = token.position();
+        return switch(token.type()) {
+            case NUMBER -> new Expr.Literal(Double.parseDouble(token.lexeme()), Type.NUMBER, position);
+            case STRING -> new Expr.Literal(token.lexeme(), Type.STRING, position);
+            case BOOLEAN -> new Expr.Literal(Boolean.parseBoolean(token.lexeme()), Type.BOOLEAN, position);
+            case IDENTIFIER -> {
+                if(current().isType(TokenType.OPEN_PAREN)) yield call(token);
+                else yield variable(token);
+            }
+            case OPEN_PAREN -> {
+                if(current().isType(TokenType.CLOSE_PAREN)) {
+                    consumeUnchecked(); // Consume ')'
+                    yield new Expr.Void(position); // () evaluates to void
+                }
+                Expr expr = expression();
+                consume("Expected ')' to close '(' located at " + position, TokenType.CLOSE_PAREN);
+                yield new Expr.Grouping(expr, position);
+            }
+            default -> throw new ParseException("Unexpected token '" + token.lexeme() + "'", position);
+        };
+    }
+    
+    private Expr call(Token identifier) {
+        String id = identifier.lexeme();
+        SourcePosition position = consume("Expected '(' to initiate function call on function '" + id + "'",
+                                          TokenType.OPEN_PAREN).position();
+        
+        List<Expr> args = new ArrayList<>();
+        while(!current().isType(TokenType.CLOSE_PAREN)) {
+            args.add(expression());
+            if(current().isType(TokenType.CLOSE_PAREN)) break;
+            consume("Expected ',' or ')' after passed argument in function call of '" + id + "'", TokenType.SEPARATOR);
+        }
+        
+        consume("Expected ')' after " + (args.size() == 0 ? "')'" : "arguments") + " in function call of '" + id + "'",
+                TokenType.CLOSE_PAREN);
+        
+        return new Expr.Call(id, args, position);
+    }
+    
+    private Expr variable(Token identifier) {
+        return new Expr.Variable(identifier.lexeme(), identifier.position());
+    }
+    
+    
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/parser/UnaryOperator.java

@@ -0,0 +1,13 @@
+package com.dfsek.terra.addons.terrascript.v2.parser;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token;
+
+
+public enum UnaryOperator {
+    NOT(Token.TokenType.BANG),
+    NEGATE(Token.TokenType.MINUS);
+    
+    public final Token.TokenType tokenType;
+    
+    UnaryOperator(Token.TokenType tokenType) { this.tokenType = tokenType; }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/semanticanalysis/FunctionReferenceAnalyzer.java

@@ -0,0 +1,166 @@
+package com.dfsek.terra.addons.terrascript.v2.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.NonexistentSymbolException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.SymbolTypeMismatchException;
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Assignment;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Binary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Call;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Grouping;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Literal;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Unary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Variable;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Void;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Block;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Break;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Continue;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Expression;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.For;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.FunctionDeclaration;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.If;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.NoOp;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Return;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.VariableDeclaration;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.While;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.UndefinedReferenceException;
+import com.dfsek.terra.addons.terrascript.v2.parser.ParseException;
+import com.dfsek.terra.api.util.generic.pair.Pair;
+
+
+public class FunctionReferenceAnalyzer implements Expr.Visitor<Void>, Stmt.Visitor<Void> {
+    
+    private final ErrorHandler errorHandler;
+    
+    public FunctionReferenceAnalyzer(ErrorHandler errorHandler) { this.errorHandler = errorHandler; }
+    
+    @Override
+    public Void visitBinaryExpr(Binary expr) {
+        expr.left.accept(this);
+        expr.right.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitGroupingExpr(Grouping expr) {
+        expr.expression.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitLiteralExpr(Literal expr) {
+        return null;
+    }
+    
+    @Override
+    public Void visitUnaryExpr(Unary expr) {
+        expr.operand.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitCallExpr(Call expr) {
+        String id = expr.identifier;
+        try {
+            expr.setSymbol(expr.getEnvironment().getFunction(expr.identifier));
+        } catch(NonexistentSymbolException e) {
+            errorHandler.add(
+                    new UndefinedReferenceException("No function by the name '" + id + "' is defined in this scope", expr.position));
+        } catch(SymbolTypeMismatchException e) {
+            errorHandler.add(new ParseException("Identifier '" + id + "' is not defined as a function", expr.position));
+        }
+        expr.arguments.forEach(e -> e.accept(this));
+        return null;
+    }
+    
+    @Override
+    public Void visitVariableExpr(Variable expr) {
+        return null;
+    }
+    
+    @Override
+    public Void visitAssignmentExpr(Assignment expr) {
+        expr.lValue.accept(this);
+        expr.rValue.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitVoidExpr(Void expr) {
+        return null;
+    }
+    
+    @Override
+    public Void visitExpressionStmt(Expression stmt) {
+        stmt.expression.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitBlockStmt(Block stmt) {
+        stmt.statements.forEach(s -> s.accept(this));
+        return null;
+    }
+    
+    @Override
+    public Void visitFunctionDeclarationStmt(FunctionDeclaration stmt) {
+        stmt.body.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitVariableDeclarationStmt(VariableDeclaration stmt) {
+        stmt.value.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitReturnStmt(Return stmt) {
+        stmt.value.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitIfStmt(If stmt) {
+        stmt.condition.accept(this);
+        stmt.trueBody.accept(this);
+        for(Pair<Expr, Block> clause : stmt.elseIfClauses) {
+            clause.getLeft().accept(this);
+            clause.getRight().accept(this);
+        }
+        stmt.elseBody.ifPresent(b -> b.accept(this));
+        return null;
+    }
+    
+    @Override
+    public Void visitForStmt(For stmt) {
+        stmt.initializer.accept(this);
+        stmt.condition.accept(this);
+        stmt.incrementer.accept(this);
+        stmt.body.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitWhileStmt(While stmt) {
+        stmt.condition.accept(this);
+        stmt.body.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitNoOpStmt(NoOp stmt) {
+        return null;
+    }
+    
+    @Override
+    public Void visitBreakStmt(Break stmt) {
+        return null;
+    }
+    
+    @Override
+    public Void visitContinueStmt(Continue stmt) {
+        return null;
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/semanticanalysis/ScopeAnalyzer.java

@@ -0,0 +1,200 @@
+package com.dfsek.terra.addons.terrascript.v2.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.Environment;
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.NonexistentSymbolException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.ScopeException.SymbolTypeMismatchException;
+import com.dfsek.terra.addons.terrascript.v2.Environment.Symbol;
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.Type;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Assignment;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Binary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Call;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Grouping;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Literal;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Unary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Variable;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Visitor;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Void;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.IdentifierAlreadyDeclaredException;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.UndefinedReferenceException;
+import com.dfsek.terra.addons.terrascript.v2.parser.ParseException;
+import com.dfsek.terra.api.util.generic.pair.Pair;
+
+
+public class ScopeAnalyzer implements Visitor<Void>, Stmt.Visitor<Void> {
+    
+    private Environment currentScope;
+    
+    private final ErrorHandler errorHandler;
+    
+    
+    public ScopeAnalyzer(Environment globalScope, ErrorHandler errorHandler) {
+        this.currentScope = globalScope;
+        this.errorHandler = errorHandler;
+    }
+    
+    @Override
+    public Void visitBinaryExpr(Binary expr) {
+        expr.right.accept(this);
+        expr.left.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitGroupingExpr(Grouping expr) {
+        expr.expression.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitLiteralExpr(Literal expr) {
+        return null;
+    }
+    
+    @Override
+    public Void visitUnaryExpr(Unary expr) {
+        expr.operand.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitCallExpr(Call expr) {
+        expr.setEnvironment(currentScope);
+        expr.arguments.forEach(e -> e.accept(this));
+        return null;
+    }
+    
+    @Override
+    public Void visitVariableExpr(Variable expr) {
+        String id = expr.identifier;
+        try {
+            expr.setSymbol(currentScope.getVariable(id));
+        } catch(NonexistentSymbolException e) {
+            errorHandler.add(
+                    new UndefinedReferenceException("No variable by the name '" + id + "' is defined in this scope", expr.position));
+        } catch(SymbolTypeMismatchException e) {
+            errorHandler.add(new ParseException("Identifier '" + id + "' is not defined as a variable", expr.position));
+        }
+        return null;
+    }
+    
+    @Override
+    public Void visitAssignmentExpr(Assignment expr) {
+        expr.lValue.accept(this);
+        expr.rValue.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitVoidExpr(Void expr) {
+        return null;
+    }
+    
+    @Override
+    public Void visitExpressionStmt(Stmt.Expression stmt) {
+        stmt.expression.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitBlockStmt(Stmt.Block stmt) {
+        currentScope = currentScope.lexicalInner();
+        stmt.statements.forEach(s -> s.accept(this));
+        currentScope = currentScope.outer();
+        return null;
+    }
+    
+    @Override
+    public Void visitFunctionDeclarationStmt(Stmt.FunctionDeclaration stmt) {
+        currentScope = currentScope.functionalInner();
+        for(Pair<String, Type> param : stmt.parameters) {
+            try {
+                currentScope.put(param.getLeft(), new Environment.Symbol.Variable(param.getRight()));
+            } catch(Environment.ScopeException.SymbolAlreadyExistsException e) {
+                throw new IllegalStateException("Formal parameter '" + param.getLeft() + "' defined in '" + stmt.identifier +
+                                                "' already exists in the function scope");
+            }
+        }
+        stmt.body.accept(this);
+        currentScope = currentScope.outer();
+        try {
+            Symbol.Function symbol = new Symbol.Function(stmt.returnType, stmt.parameters.stream().map(Pair::getRight).toList(), currentScope);
+            stmt.setSymbol(symbol);
+            currentScope.put(stmt.identifier, symbol);
+        } catch(Environment.ScopeException.SymbolAlreadyExistsException e) {
+            errorHandler.add(new IdentifierAlreadyDeclaredException("Name '" + stmt.identifier + "' is already defined in this scope",
+                                                                    stmt.position));
+        }
+        return null;
+    }
+    
+    @Override
+    public Void visitVariableDeclarationStmt(Stmt.VariableDeclaration stmt) {
+        stmt.value.accept(this);
+        try {
+            currentScope.put(stmt.identifier, new Environment.Symbol.Variable(stmt.type));
+        } catch(Environment.ScopeException.SymbolAlreadyExistsException e) {
+            errorHandler.add(new IdentifierAlreadyDeclaredException("Name '" + stmt.identifier + "' is already defined in this scope",
+                                                                    stmt.position));
+        }
+        return null;
+    }
+    
+    @Override
+    public Void visitReturnStmt(Stmt.Return stmt) {
+        stmt.value.accept(this);
+        return null;
+    }
+    
+    @Override
+    public Void visitIfStmt(Stmt.If stmt) {
+        stmt.condition.accept(this);
+        stmt.trueBody.accept(this);
+        for(Pair<Expr, Stmt.Block> clause : stmt.elseIfClauses) {
+            clause.getLeft().accept(this);
+            clause.getRight().accept(this);
+        }
+        stmt.elseBody.ifPresent(b -> b.accept(this));
+        return null;
+    }
+    
+    @Override
+    public Expr.Void visitForStmt(Stmt.For stmt) {
+        currentScope = currentScope.loopInner(); // Loop initializer, condition, and incrementer belong to inner scope
+        
+        stmt.initializer.accept(this);
+        stmt.condition.accept(this);
+        stmt.incrementer.accept(this);
+        stmt.body.accept(this);
+        
+        currentScope = currentScope.outer();
+        return null;
+    }
+    
+    @Override
+    public Expr.Void visitWhileStmt(Stmt.While stmt) {
+        stmt.condition.accept(this);
+        currentScope = currentScope.loopInner();
+        stmt.body.accept(this);
+        currentScope = currentScope.outer();
+        return null;
+    }
+    
+    @Override
+    public Expr.Void visitNoOpStmt(Stmt.NoOp stmt) {
+        return null;
+    }
+    
+    @Override
+    public Expr.Void visitBreakStmt(Stmt.Break stmt) {
+        return null;
+    }
+    
+    @Override
+    public Expr.Void visitContinueStmt(Stmt.Continue stmt) {
+        return null;
+    }
+    
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/semanticanalysis/SemanticAnalyzer.java

@@ -0,0 +1,24 @@
+package com.dfsek.terra.addons.terrascript.v2.semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.Environment;
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt;
+
+
+public class SemanticAnalyzer {
+    
+    public static TypedStmt.Block analyze(Stmt.Block root, ErrorHandler errorHandler) throws Exception {
+        new ScopeAnalyzer(Environment.global(), errorHandler).visitBlockStmt(root);
+        errorHandler.throwAny();
+        
+        new FunctionReferenceAnalyzer(errorHandler).visitBlockStmt(root);
+        errorHandler.throwAny();
+        
+        TypedStmt.Block checkedRoot = (TypedStmt.Block) new TypeChecker(errorHandler).visitBlockStmt(root);
+        errorHandler.throwAny();
+        
+        return checkedRoot;
+    }
+    
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/semanticanalysis/TypeChecker.java

@@ -0,0 +1,258 @@
+package com.dfsek.terra.addons.terrascript.v2.semanticanalysis;
+
+import java.util.List;
+import java.util.Optional;
+
+import com.dfsek.terra.addons.terrascript.v2.Environment;
+import com.dfsek.terra.addons.terrascript.v2.Environment.Symbol;
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.Type;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Assignment;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Binary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Call;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Grouping;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Literal;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Unary;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Variable;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Visitor;
+import com.dfsek.terra.addons.terrascript.v2.ast.Expr.Void;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedExpr;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.InvalidFunctionDeclarationException;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.InvalidTypeException;
+import com.dfsek.terra.addons.terrascript.v2.parser.ParseException;
+import com.dfsek.terra.api.util.generic.pair.Pair;
+
+import static com.dfsek.terra.addons.terrascript.v2.util.OrdinalUtil.ordinalOf;
+
+
+public class TypeChecker implements Visitor<TypedExpr>, Stmt.Visitor<TypedStmt> {
+    
+    private final ErrorHandler errorHandler;
+    
+    TypeChecker(ErrorHandler errorHandler) { this.errorHandler = errorHandler; }
+    
+    private static String scopedIdentifier(String identifier, Symbol.Function symbol) {
+        return identifier + "$" + symbol.scope.name;
+    }
+    
+    @Override
+    public TypedExpr visitBinaryExpr(Binary expr) {
+        TypedExpr left = expr.left.accept(this);
+        TypedExpr right = expr.right.accept(this);
+        
+        Type leftType = left.type;
+        Type rightType = right.type;
+        
+        Type type = switch(expr.operator) {
+            case BOOLEAN_OR, BOOLEAN_AND -> {
+                if(!leftType.typeOf(Type.BOOLEAN) || !rightType.typeOf(Type.BOOLEAN))
+                    errorHandler.add(new InvalidTypeException("Both operands of '" + expr.operator + "' operator must be of type '" + Type.BOOLEAN + "', found types '" + leftType + "' and '" + rightType + "'", expr.position));
+                yield Type.BOOLEAN;
+            }
+            case EQUALS, NOT_EQUALS -> {
+                if(!leftType.typeOf(rightType)) errorHandler.add(new InvalidTypeException("Both operands of equality operator (==) must be of the same type, found mismatched types '" + leftType + "' and '" + rightType + "'", expr.position));
+                yield Type.BOOLEAN;
+            }
+            case GREATER, GREATER_EQUALS, LESS, LESS_EQUALS -> {
+                if(!leftType.typeOf(Type.NUMBER) || !rightType.typeOf(Type.NUMBER))
+                    errorHandler.add(new InvalidTypeException("Both operands of '" + expr.operator + "' operator must be of type '" + Type.NUMBER + "', found types '" + leftType + "' and '" + rightType + "'", expr.position));
+                yield Type.BOOLEAN;
+            }
+            case ADD -> {
+                if(leftType.typeOf(Type.NUMBER) && rightType.typeOf(Type.NUMBER)) {
+                    yield Type.NUMBER;
+                }
+                if(leftType.typeOf(Type.STRING) || rightType.typeOf(Type.STRING)) {
+                    yield Type.STRING;
+                }
+                errorHandler.add(new RuntimeException("Addition operands must be either both of type '" + Type.NUMBER + "', or one of type '" + Type.STRING + "'"));
+                yield Type.VOID;
+            }
+            case SUBTRACT, MULTIPLY, DIVIDE, MODULO -> {
+                if(!leftType.typeOf(Type.NUMBER) || !rightType.typeOf(Type.NUMBER))
+                    errorHandler.add(new InvalidTypeException("Both operands of '" + expr.operator + "' operator must be of type '" + Type.NUMBER + "', found types '" + leftType + "' and '" + rightType + "'", expr.position));
+                yield Type.NUMBER;
+            }
+        };
+        return new TypedExpr.Binary(left, expr.operator, right, type);
+    }
+    
+    @Override
+    public TypedExpr visitGroupingExpr(Grouping expr) {
+        return expr.expression.accept(this);
+    }
+    
+    @Override
+    public TypedExpr visitLiteralExpr(Literal expr) {
+        return new TypedExpr.Literal(expr.value, expr.type);
+    }
+    
+    @Override
+    public TypedExpr visitUnaryExpr(Unary expr) {
+        TypedExpr right = expr.operand.accept(this);
+        Type type = switch(expr.operator) {
+            case NOT -> {
+                if(!right.type.typeOf(Type.BOOLEAN)) throw new RuntimeException();
+                yield Type.BOOLEAN;
+            }
+            case NEGATE -> {
+                if(!right.type.typeOf(Type.NUMBER)) throw new RuntimeException();
+                yield Type.NUMBER;
+            }
+        };
+        return new TypedExpr.Unary(expr.operator, right, type);
+    }
+    
+    @Override
+    public TypedExpr visitCallExpr(Call expr) {
+        String id = expr.identifier;
+        
+        Environment.Symbol.Function signature = expr.getSymbol();
+        
+        List<TypedExpr> arguments = expr.arguments.stream().map(a -> a.accept(this)).toList();
+        List<Type> parameters = signature.parameters;
+        
+        if(arguments.size() != parameters.size())
+            errorHandler.add(new ParseException(
+                    "Provided " + arguments.size() + " arguments to function call of '" + id + "', expected " + parameters.size() +
+                    " arguments", expr.position));
+        
+        for(int i = 0; i < parameters.size(); i++) {
+            Type expectedType = parameters.get(i);
+            Type providedType = arguments.get(i).type;
+            if(!expectedType.typeOf(providedType))
+                errorHandler.add(new InvalidTypeException(
+                        ordinalOf(i + 1) + " argument provided for function '" + id + "' expects type " + expectedType + ", found " +
+                        providedType + " instead", expr.position));
+        }
+        
+        return new TypedExpr.Call(expr.identifier, arguments, scopedIdentifier(expr.identifier, expr.getSymbol()), signature.type);
+    }
+    
+    @Override
+    public TypedExpr visitVariableExpr(Variable expr) {
+        return new TypedExpr.Variable(expr.identifier, expr.getSymbol().type);
+    }
+    
+    @Override
+    public TypedExpr visitAssignmentExpr(Assignment expr) {
+        TypedExpr.Variable left = (TypedExpr.Variable) expr.lValue.accept(this);
+        TypedExpr right = expr.rValue.accept(this);
+        Type expected = left.type;
+        String id = expr.lValue.identifier;
+        if(!right.type.typeOf(expected))
+            errorHandler.add(new InvalidTypeException(
+                    "Cannot assign variable '" + id + "' to value of type " + right.type + ", '" + id + "' is declared with type " + expected,
+                    expr.position));
+        return new TypedExpr.Assignment(left, right, right.type);
+    }
+    
+    @Override
+    public TypedExpr visitVoidExpr(Void expr) {
+        return new TypedExpr.Void(Type.VOID);
+    }
+    
+    @Override
+    public TypedStmt visitExpressionStmt(Stmt.Expression stmt) {
+        return new TypedStmt.Expression(stmt.expression.accept(this));
+    }
+    
+    @Override
+    public TypedStmt visitBlockStmt(Stmt.Block stmt) {
+        return new TypedStmt.Block(stmt.statements.stream().map(s -> s.accept(this)).toList());
+    }
+    
+    @Override
+    public TypedStmt visitFunctionDeclarationStmt(Stmt.FunctionDeclaration stmt) {
+        TypedStmt.Block body = new TypedStmt.Block(stmt.body.statements.stream().map(s -> s.accept(this)).toList());
+        boolean hasReturn = alwaysReturns(body, stmt);
+        if(!stmt.returnType.typeOf(Type.VOID) && !hasReturn) {
+            errorHandler.add(
+                    new InvalidFunctionDeclarationException("Function body for '" + stmt.identifier + "' does not contain return statement",
+                                                            stmt.position));
+        }
+        return new TypedStmt.FunctionDeclaration(stmt.identifier, stmt.parameters, stmt.returnType, body, scopedIdentifier(stmt.identifier, stmt.getSymbol()));
+    }
+    
+    private boolean alwaysReturns(TypedStmt stmt, Stmt.FunctionDeclaration function) {
+        if(stmt instanceof TypedStmt.Return ret) {
+            if(!ret.value.type.typeOf(function.returnType))
+                errorHandler.add(new InvalidTypeException(
+                        "Return statement must match function's return type. Function '" + function.identifier + "' expects " +
+                        function.returnType + ", found " + ret.value.type + " instead", function.position));
+            return true;
+        } else if (stmt instanceof TypedStmt.If ifStmt) {
+            return alwaysReturns(ifStmt.trueBody, function) &&
+                   ifStmt.elseIfClauses.stream().map(Pair::getRight).allMatch(s -> alwaysReturns(s, function)) &&
+                   ifStmt.elseBody.map(body -> alwaysReturns(body, function)).orElse(false); // If else body is not defined then statement does not always return
+        } else if (stmt instanceof TypedStmt.Block block) {
+            return block.statements.stream().anyMatch(s -> alwaysReturns(s, function));
+        }
+        return false;
+    }
+    
+    @Override
+    public TypedStmt visitVariableDeclarationStmt(Stmt.VariableDeclaration stmt) {
+        TypedExpr value = stmt.value.accept(this);
+        if(!stmt.type.typeOf(value.type))
+            errorHandler.add(new InvalidTypeException(
+                    "Type of value assigned to variable '" + stmt.identifier + "' does not match variable's declared type. Expected type '" +
+                    stmt.type + "', found '" + value.type +"' instead", stmt.position));
+        return new TypedStmt.VariableDeclaration(stmt.type, stmt.identifier, value);
+    }
+    
+    @Override
+    public TypedStmt visitReturnStmt(Stmt.Return stmt) {
+        return new TypedStmt.Return(stmt.value.accept(this));
+    }
+    
+    @Override
+    public TypedStmt visitIfStmt(Stmt.If stmt) {
+        TypedExpr condition = stmt.condition.accept(this);
+        if(!condition.type.typeOf(Type.BOOLEAN)) errorHandler.add(new InvalidTypeException("If statement conditional must be of type '" + Type.BOOLEAN + "', found '" + condition.type + "' instead.", stmt.position));
+        
+        TypedStmt.Block trueBody = (TypedStmt.Block) stmt.trueBody.accept(this);
+        List<Pair<TypedExpr, TypedStmt.Block>> elseIfClauses = stmt.elseIfClauses.stream().map(c -> {
+            TypedExpr clauseCondition = c.getLeft().accept(this);
+            if (!clauseCondition.type.typeOf(Type.BOOLEAN)) errorHandler.add(new InvalidTypeException("Else if clause conditional must be of type '" + Type.BOOLEAN + "', found '" + condition.type + "' instead.", stmt.position));
+            return Pair.of(clauseCondition, (TypedStmt.Block) c.getRight().accept(this));
+        }).toList();
+        
+        Optional<TypedStmt.Block> elseBody = stmt.elseBody.map(b -> (TypedStmt.Block) b.accept(this));
+        
+        return new TypedStmt.If(condition, trueBody, elseIfClauses, elseBody);
+    }
+    
+    @Override
+    public TypedStmt visitForStmt(Stmt.For stmt) {
+        TypedStmt initializer = stmt.initializer.accept(this);
+        TypedExpr condition = stmt.condition.accept(this);
+        if(!condition.type.typeOf(Type.BOOLEAN)) errorHandler.add(new InvalidTypeException("For statement conditional must be of type '" + Type.BOOLEAN + "', found '" + condition.type + "' instead.", stmt.position));
+        TypedExpr incrementer = stmt.incrementer.accept(this);
+        return new TypedStmt.For(initializer, condition, incrementer, (TypedStmt.Block) stmt.body.accept(this));
+    }
+    
+    @Override
+    public TypedStmt visitWhileStmt(Stmt.While stmt) {
+        TypedExpr condition = stmt.condition.accept(this);
+        if(!condition.type.typeOf(Type.BOOLEAN)) errorHandler.add(new InvalidTypeException("While statement conditional must be of type '" + Type.BOOLEAN + "', found '" + condition.type + "' instead.", stmt.position));
+        return new TypedStmt.While(condition, (TypedStmt.Block) stmt.body.accept(this));
+    }
+    
+    @Override
+    public TypedStmt visitNoOpStmt(Stmt.NoOp stmt) {
+        return new TypedStmt.NoOp();
+    }
+    
+    @Override
+    public TypedStmt visitBreakStmt(Stmt.Break stmt) {
+        return new TypedStmt.Break();
+    }
+    
+    @Override
+    public TypedStmt visitContinueStmt(Stmt.Continue stmt) {
+        return new TypedStmt.Continue();
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/util/ASMUtil.java

@@ -0,0 +1,20 @@
+package com.dfsek.terra.addons.terrascript.v2.util;
+
+import com.dfsek.terra.addons.terrascript.v2.Type;
+
+
+public class ASMUtil {
+    
+    /**
+     * Dynamically get name to account for possibility of shading
+     * @param clazz Class instance
+     * @return Internal class name
+     */
+    public static String dynamicName(Class<?> clazz) {
+        return clazz.getCanonicalName().replace('.', '/');
+    }
+    
+    public static org.objectweb.asm.Type tsTypeToAsmType(Type type) {
+        return org.objectweb.asm.Type.getType((Class<?>) type.javaType());
+    }
+}

common/addons/structure-terrascript-v2/src/main/java/com/dfsek/terra/addons/terrascript/v2/util/OrdinalUtil.java

@@ -0,0 +1,11 @@
+package com.dfsek.terra.addons.terrascript.v2.util;
+
+public class OrdinalUtil {
+    public static String ordinalOf(int i) {
+        String[] suffixes = new String[]{ "th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th" };
+        return switch(i % 100) {
+            case 11, 12, 13 -> i + "th";
+            default -> i + suffixes[i % 10];
+        };
+    }
+}

common/addons/structure-terrascript-v2/src/main/resources/terra.addon.yml

@@ -0,0 +1,12 @@
+schema-version: 1
+contributors:
+  - Terra contributors
+id: structure-terrascript-v2
+version: @VERSION@
+entrypoints:
+  - "com.dfsek.terra.addons.terrascript.v2.TerraScript2Addon"
+website:
+  issues: https://github.com/PolyhedralDev/Terra/issues
+  source: https://github.com/PolyhedralDev/Terra
+  docs: https://terra.polydev.org
+license: MIT License

common/addons/structure-terrascript-v2/src/test/java/codegen/CodeGenTest.java

@@ -0,0 +1,118 @@
+package codegen;
+
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.ast.Stmt.Block;
+import com.dfsek.terra.addons.terrascript.v2.ast.TypedStmt;
+import com.dfsek.terra.addons.terrascript.v2.codegen.TerraScript;
+import com.dfsek.terra.addons.terrascript.v2.codegen.asm.TerraScriptClassGenerator;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Lexer;
+import com.dfsek.terra.addons.terrascript.v2.parser.Parser;
+import com.dfsek.terra.addons.terrascript.v2.semanticanalysis.SemanticAnalyzer;
+
+import org.junit.jupiter.api.Test;
+
+
+public class CodeGenTest {
+    
+    @Test
+    public void test() {
+        testValid("""
+                  printNum(12345);
+                  
+                  if (1 == 1) print("Dis is true");
+                  
+                  var a: num = 1;
+                  var b: num = 2;
+                  var e: str = "test";
+                  
+                  if (a <= b) {
+                      print("a is <= b");
+                  } else {
+                      print("a is not <= b");
+                  }
+                  
+                  if (e == "foo") {
+                      print("e is == foo");
+                  } else if (e == "bar") {
+                      print("e is == bar");
+                  } else {
+                      print("e is not foo or bar");
+                  }
+                  
+                  if (true && false || (false && true)) {
+                      print("Thin is tru");
+                  } else {
+                      print("Thin is not tru :(");
+                  }
+                  
+                  fun loopTwiceThenBreak() {
+                      var i: num = 0;
+                      while (true) {
+                          print("looped");
+                          if (i == 1) break;
+                          i = i + 1;
+                      }
+                  }
+                  
+                  print("Should loop twice:");
+                  loopTwiceThenBreak();
+                  
+                  retNum();
+                  var bln: bool = true;
+              
+                  print(takesArgs("test", 3, true));
+                  print(retStr());
+                  
+                  doStuff("Ayo", "world", true);
+                  
+                  fun retNum(): num {
+                      return 3 + 3;
+                  }
+                  
+                  fun retBool(): bool {
+                      return true;
+                  }
+                  
+                  fun concatThree(a: str, b: str, c: str): str {
+                      fun concatTwo(a: str, b: str): str {
+                          return a + b;
+                      }
+                      return concatTwo(a, b) + c;
+                  }
+                  
+                  fun retStr(): str {
+                      fun concatTwo(a: str, b: str): str {
+                          return a + b;
+                      }
+                      var hello: str = "Hell";
+                      hello = concatTwo(hello, "o");
+                      var world: str = "world!";
+                      return concatThree(hello, " ", world);
+                  }
+                  
+                  fun takesArgs(a: str, b: num, c: bool): str {
+                      return a;
+                  }
+                  
+                  fun doStuff(a: str, b: str, c: bool) {
+                      print("Doing stuff");
+                      if (c) {
+                          print(concatThree(a, " ", b));
+                      } else {
+                          print("c is false");
+                      }
+                  }
+                  """);
+    }
+    
+    private void testValid(String validSource) {
+        try {
+            Block script = Parser.parse(new Lexer(validSource).analyze());
+            TypedStmt.Block typedScript = SemanticAnalyzer.analyze(script, new ErrorHandler());
+            TerraScript ts = new TerraScriptClassGenerator("./build/codegentest").generate(typedScript);
+            ts.execute();
+        } catch(Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

common/addons/structure-terrascript-v2/src/test/java/lexer/LexerTest.java

@@ -0,0 +1,34 @@
+package lexer;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.Lexer;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.Token.TokenType;
+
+import org.junit.jupiter.api.Test;
+
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class LexerTest {
+    
+    private static void tokenTypeTest(String input, TokenType type) {
+        Lexer lexer = new Lexer(input);
+        assertEquals(new Token(input, type, new SourcePosition(1, 1)), lexer.current());
+    }
+    
+    @Test
+    public void typeTest() {
+        tokenTypeTest("identifier", TokenType.IDENTIFIER);
+        tokenTypeTest("(", TokenType.OPEN_PAREN);
+        tokenTypeTest(")", TokenType.CLOSE_PAREN);
+    }
+    
+    @Test
+    public void multipleTokensTest() {
+        Lexer lexer = new Lexer("(3 + 2)");
+        lexer.analyze().forEach(System.out::println);
+    }
+}

common/addons/structure-terrascript-v2/src/test/java/lexer/LookaheadStreamTest.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2020-2021 Polyhedral Development
+ *
+ * The Terra Core Addons are licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in this module's root directory.
+ */
+
+package lexer;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.LookaheadStream;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Char;
+
+import com.dfsek.terra.addons.terrascript.v2.lexer.SourcePosition;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+
+public class LookaheadStreamTest {
+    @Test
+    public void lookahead() {
+        String testString = "Test string...\nNew line";
+        
+        LookaheadStream lookahead = new LookaheadStream(testString);
+        
+        Char first = new Char('T', new SourcePosition(1, 1));
+        Char second = new Char('e', new SourcePosition(1, 2));
+        Char third = new Char('s', new SourcePosition(1, 3));
+        Char space = new Char(' ', new SourcePosition(1, 5));
+        Char newline = new Char('\n', new SourcePosition(1, 15));
+        Char lineTwoColOne = new Char('N', new SourcePosition(2, 1));
+        String lineTwo = "New line";
+        
+        assertTrue(lookahead.matchesString("Test", false));
+        assertTrue(lookahead.matchesString(testString, false));
+        assertFalse(lookahead.matchesString(testString + "asdf", false));
+        assertFalse(lookahead.matchesString("Foo", false));
+        
+        assertEquals(first, lookahead.current());
+        assertEquals(first, lookahead.current());
+
+        assertEquals(new SourcePosition(1, 1), lookahead.getPosition());
+        assertEquals(new SourcePosition(1, 1), lookahead.getPosition());
+        
+        assertEquals(second, lookahead.peek());
+        assertEquals(second, lookahead.peek());
+        
+        assertEquals(first, lookahead.consume());
+        
+        assertFalse(lookahead.matchesString(testString, false));
+        
+        assertEquals(second, lookahead.current());
+        
+        assertEquals(second, lookahead.consume());
+
+        assertEquals(third, lookahead.current());
+        
+        assertTrue(lookahead.matchesString("st", true));
+        
+        assertEquals(space, lookahead.current());
+        
+        assertEquals(space, lookahead.consume());
+        
+        assertTrue(lookahead.matchesString("string...", false));
+        assertTrue(lookahead.matchesString("string...", true));
+        assertFalse(lookahead.matchesString("string...", false));
+        
+        assertEquals(newline, lookahead.current());
+        assertEquals(newline, lookahead.consume());
+        
+        assertEquals(lineTwoColOne, lookahead.current());
+        
+        assertTrue(lookahead.matchesString(lineTwo, false));
+        assertFalse(lookahead.matchesString(lineTwo + "asdf", false));
+        assertTrue(lookahead.matchesString(lineTwo, true));
+        
+        assertEquals(new SourcePosition(2, 8), lookahead.getPosition());
+        
+        assertDoesNotThrow(lookahead::consume);
+        assertEquals(new SourcePosition(2, 8), lookahead.getPosition());
+        
+        assertDoesNotThrow(lookahead::consume);
+        assertEquals(new SourcePosition(2, 8), lookahead.getPosition());
+    }
+}

common/addons/structure-terrascript-v2/src/test/java/semanticanalysis/SemanticAnalyzerTest.java

@@ -0,0 +1,365 @@
+package semanticanalysis;
+
+import com.dfsek.terra.addons.terrascript.v2.ErrorHandler;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.IdentifierAlreadyDeclaredException;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.UndefinedReferenceException;
+import com.dfsek.terra.addons.terrascript.v2.semanticanalysis.SemanticAnalyzer;
+import com.dfsek.terra.addons.terrascript.v2.lexer.Lexer;
+import com.dfsek.terra.addons.terrascript.v2.parser.Parser;
+
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.InvalidFunctionDeclarationException;
+import com.dfsek.terra.addons.terrascript.v2.exception.semanticanalysis.InvalidTypeException;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+
+public class SemanticAnalyzerTest {
+    
+    @Test
+    public void testVariableReference() {
+        // Use of declared variable
+        testValid("var a: num = 1; a + a;");
+        
+        // Can't use undeclared variable
+        testInvalid("a + a;", UndefinedReferenceException.class);
+        
+        // Can't reference variable before declaration
+        testInvalid("a + a; var a: num = 1;", UndefinedReferenceException.class);
+        
+        // Variable declarations shouldn't be accessible from inner scopes
+        testInvalid("{ var a: num = 1; } a + a;", UndefinedReferenceException.class);
+        
+        // Can access variables declared in outer scope
+        testValid("var a: num = 3; { a + a; }");
+        
+        // Should not be able to use variables from outer scope if they're declared after scope
+        testInvalid("{ a + a; } var a: num = 2;", UndefinedReferenceException.class);
+        
+        // Can't use undeclared variable as function argument
+        testInvalid("fun test(p: str) {} test(a);", UndefinedReferenceException.class);
+        
+        // Same as above, but in inner scope
+        testInvalid("fun test(p: str) {} { test(a); }", UndefinedReferenceException.class);
+        
+        // Cannot assign undeclared variable
+        testInvalid("a = 1;", UndefinedReferenceException.class);
+        
+        // Cannot assign to variable declared after assignment
+        testInvalid("a = 2; var a: num = 1;", UndefinedReferenceException.class);
+    }
+    
+    @Test
+    public void testAssignment() {
+        // Simple assignment
+        testValid("var a: num = 1; a = 2;");
+        
+        // Can assign variables declared in outer scope
+        testValid("""
+                  var a: num = 1;
+                  { a = 2; }
+                  """);
+        
+        // Cannot assign variables declared in inner scope
+        testInvalid("""
+                    { var a: num = 1; }
+                    a = 2;
+                    """, UndefinedReferenceException.class);
+        
+        // Cannot assign variables declared in outer scope after reference
+        testInvalid("""
+                    { a = 2; }
+                    var a: num = 1;
+                    """, UndefinedReferenceException.class);
+        
+        // Cannot assign variable to expression of different type
+        testInvalid("var a: num = 1; a = true;", InvalidTypeException.class);
+    }
+    
+    @Test
+    public void testReturnStatement() {
+        // Function return must match signature
+        testInvalid("fun returnBool(): bool {}", InvalidFunctionDeclarationException.class);
+        testInvalid("fun returnNum(): num { return \"Not num\"; }", InvalidTypeException.class);
+        
+        // Return statements can be empty for void return
+        testValid("fun returnVoid() { return; }");
+        
+        // Return statement returns type matching function signature
+        testValid("fun returnNum(): num { return 3; }");
+        
+        testValid("fun returnVoid() { return (); }");
+    }
+    
+    @Test
+    public void testFunctionReturnControlFlowAnalysis() {
+        // Non-void returning function bodies must contain at least one statement that always returns
+        testInvalid("""
+                    fun returnsNum(): num {
+                    }
+                    """, InvalidFunctionDeclarationException.class);
+        
+        testValid("""
+                  fun returnsNum(): num {
+                      return 1;
+                  }
+                  """);
+        
+        testValid("""
+                  fun returnsNum(): num {
+                      1 + 1;
+                      return 1;
+                  }
+                  """);
+        
+        // Statements after the first always-return-statement are unreachable, unreachable code is legal
+        testValid("""
+                  fun returnsNum(): num {
+                      return 1;
+                      1 + 1; // Unreachable
+                  }
+                  """);
+        
+        // Void returning functions can omit returns
+        testValid("""
+                  fun returnsNothing() {
+                  }
+                  """);
+        
+        // Returns can still be explicitly used for void returning functions
+        testValid("""
+                    fun returnsNum(p: bool) {
+                        if (p) {
+                            return;
+                        }
+                    }
+                    """);
+        
+        // If all if-statement bodies always return, then the statement is considered as always returning
+        testValid("""
+                  fun returnsNum(p: bool): num {
+                      if (p) {
+                          return 1;
+                      } else {
+                          return 0;
+                      }
+                  }
+                  """);
+        
+        testValid("""
+                  fun returnsNum(p1: bool, p2: bool): num {
+                      if (p1) {
+                          return 1;
+                      } else if (p2) {
+                          return 2;
+                      } else {
+                          return 3;
+                      }
+                  }
+                  """);
+        
+        // If no else body is defined, an if-statement does not always return, therefore the function does not contain any always-return-statements
+        testInvalid("""
+                    fun returnsNum(p: bool): num {
+                        if (p) {
+                            return 1;
+                        }
+                    }
+                    """, InvalidFunctionDeclarationException.class);
+        
+        testInvalid("""
+                    fun returnsNum(p1: bool, p2: bool): num {
+                        if (p1) {
+                            return 1;
+                        } else if (p2) {
+                            return 2;
+                        }
+                    }
+                    """, InvalidFunctionDeclarationException.class);
+        
+        // Nested ifs should work
+        testValid("""
+                  fun returnsNum(p1: bool, p2: bool): num {
+                      if (p1) {
+                          if (p2) {
+                              return 1;
+                          } else {
+                              return 2;
+                          }
+                      } else {
+                          return 3;
+                      }
+                  }
+                  """);
+        
+        testInvalid("""
+                  fun returnsNum(p1: bool, p2: bool): num {
+                      if (p1) {
+                          if (p2) {
+                              return 1;
+                          }
+                          // No else clause here, so will not always return
+                      } else {
+                          return 3;
+                      }
+                  }
+                  """, InvalidFunctionDeclarationException.class);
+        
+        // If-statement may not always return but a return statement after it means function will always return
+        testValid("""
+                    fun returnsNum(p: bool): num {
+                        if (p) {
+                            return 1;
+                        }
+                        return 2;
+                    }
+                    """);
+        
+        // Same applies when statements are swapped
+        testValid("""
+                    fun returnsNum(p: bool): num {
+                        return 1;
+                        // Unreachable
+                        if (p) {
+                            return 2;
+                        }
+                    }
+                    """);
+    }
+    
+    @Test
+    public void testFunctionCall() {
+        // Simple function declaration then call
+        testValid("fun test() {}; test();");
+        
+        // Can be used before declaration
+        testValid("test(); fun test() {};");
+        
+        // Can be used from outer scope
+        testValid("fun test() {}; { test(); }");
+        
+        // Can be used from outer scope before declaration
+        testValid("{ test(); } fun test() {};");
+        
+        // Can be used in many outer scopes
+        testValid("{{{{{ test(); }}}}} fun test() {};");
+        
+        // Calling function that hasn't been declared
+        testInvalid("test();", UndefinedReferenceException.class);
+        
+        // Cannot use functions declared in inner scopes
+        testInvalid("{ fun test() {} } test();", UndefinedReferenceException.class);
+        testInvalid("test(); { fun test() {} }", UndefinedReferenceException.class);
+        
+        // Mutual recursion supported
+        testValid("fun a() { b(); } fun b() { a(); }");
+    }
+    
+    @Test
+    public void testFunctionArgumentPassing() {
+        // Simple argument passing
+        testValid("fun test(p: num); test(1);");
+        
+        // Passing multiple arguments
+        testValid("fun test(p1: num, p2: bool); test(1, false);");
+        
+        // Argument type must match parameter type
+        testInvalid("fun test(p: num); test(false);", InvalidTypeException.class);
+        
+        // Function return
+        testValid("""
+                  fun returnBool(): bool {
+                      return true;
+                  }
+                  fun takeBool(p: bool) {}
+                  takeBool(returnBool());
+                  """);
+        
+        // Should not be able to pass argument of type not matching parameter type
+        testInvalid("""
+                  fun returnBool(): bool {
+                      return true;
+                  }
+                  fun takeNum(p: num) {}
+                  takeNum(returnBool());
+                  """, InvalidTypeException.class);
+    }
+    
+    @Test
+    public void testParameterUse() {
+        // Function bodies should be able to use parameter names
+        testValid("fun test(a: num, b: num) { a + b; }");
+        testInvalid("fun test(a: num, b: num) { a + c; }", UndefinedReferenceException.class);
+        
+        // Function bodies can't use variables from outer scope
+        testInvalid("var a: num = 1; fun doStuff() { a + 2; }", UndefinedReferenceException.class);
+        testInvalid("fun doStuff() { a + 2; } var a: num = 1;", UndefinedReferenceException.class);
+        
+        // Type checking parameters
+        testValid("fun takesNum(a: num) {} fun test(numberParam: num) { takesNum(numberParam); }");
+        testInvalid("fun takesNum(a: num) {} fun test(boolParam: bool) { takesNum(boolParam); }", InvalidTypeException.class);
+    }
+    
+    @Test
+    public void testShadowing() {
+        // Can't shadow variable in immediate scope
+        testInvalid("var a: num = 1; var a: num = 2;", IdentifierAlreadyDeclaredException.class);
+        
+        // Can shadow variable from outer scope
+        testValid("var a: num = 1; { var a: num = 2; }");
+        
+        // Can declare variable after same identifier is used previously in an inner scope
+        testValid("{ var a: num = 2; } var a: num = 1;");
+        
+        // Ensure shadowed variable type is used
+        testValid("""
+                  fun takesNum(p: num) {}
+                  var a: bool = false;
+                  {
+                      var a: num = 1;
+                      takesNum(a);
+                  }
+                  """);
+        
+        // Should not be able to use type of shadowed variable in use of shadowing variable
+        testInvalid("""
+                  fun takesNum(p: num) {}
+                  var a: num = false;
+                  {
+                      var a: bool = 1;
+                      takesNum(a);
+                  }
+                  """, InvalidTypeException.class);
+        
+        // Functions can be shadowed in inner scopes
+        testValid("""
+                  fun test() {}
+                  {
+                    fun test() {}
+                  }
+                  {
+                    fun test() {}
+                  }
+                  """);
+        
+        // Functions can't be shadowed in the same immediate scope
+        testInvalid("""
+                  fun test() {}
+                  fun test() {}
+                  """, IdentifierAlreadyDeclaredException.class);
+        
+        // Can't use function name that is already declared as a variable
+        testInvalid("var id: num = 1; fun id() {}", IdentifierAlreadyDeclaredException.class);
+    }
+    
+    private <T extends Exception> void testInvalid(String invalidSource, Class<T> exceptionType) {
+        ErrorHandler errorHandler = new ErrorHandler();
+        assertThrows(exceptionType, () -> SemanticAnalyzer.analyze(Parser.parse(new Lexer(invalidSource).analyze()), errorHandler));
+    }
+    
+    private void testValid(String validSource) {
+        ErrorHandler errorHandler = new ErrorHandler();
+        assertDoesNotThrow(() -> SemanticAnalyzer.analyze(Parser.parse(new Lexer(validSource).analyze()), errorHandler));
+    }
+}