implement a bunch of function utils

This commit is contained in:
dfsek
2026-01-03 15:53:13 -07:00
parent 65eb66c3ca
commit e6300df185
5 changed files with 78 additions and 65 deletions

View File

@@ -16,6 +16,7 @@ import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.IntStream;
import java.util.stream.Stream;
import static com.dfsek.terra.api.util.function.FunctionUtils.*;
public class BiomeLocator {
@@ -76,7 +77,7 @@ public class BiomeLocator {
.mapToObj(z -> new int[]{ minX, z }); // Fixed X (min), varying Z
Optional<Either<Vector3Int, Vector2Int>> ringResult = Stream.of(northSide, eastSide, southSide, westSide)
.flatMap(Function.identity())
.flatMap(identity())
.parallel()
.map(coords -> check(
provider,
@@ -93,10 +94,10 @@ public class BiomeLocator {
.findFirst(); // findFirst() respects encounter order (North -> East -> South -> West)
if(ringResult.isPresent()) {
return Maybe.fromOptional(ringResult);
return fromOptional(ringResult);
}
}
return Maybe.nothing();
return nothing();
});
}
@@ -120,16 +121,16 @@ public class BiomeLocator {
// Iterate from bottom to top of the world using the step
for(int y = minHeight; y < maxHeight; y += step) {
if(filter.test(provider.getBiome(x, y, z, seed))) {
return Maybe.just(Either.left(Vector3Int.of(x, y, z)));
return just(left(Vector3Int.of(x, y, z)));
}
}
return Maybe.nothing();
return nothing();
} else {
// 2D Mode: Check only the base biome
// We use a flatMap approach here to be safe with Optionals inside the stream
return provider.getBaseBiome(x, z, seed)
.filter(filter)
.map(b -> Either.right(Vector2Int.of(x, z)));
.map(b -> right(Vector2Int.of(x, z)));
}
}
}

View File

@@ -29,6 +29,7 @@ import java.util.function.Function;
import com.dfsek.terra.api.registry.key.RegistryKey;
import com.dfsek.terra.api.util.reflection.TypeKey;
import static com.dfsek.terra.api.util.function.FunctionUtils.*;
public interface Registry<T> extends TypeLoader<T> {
@@ -96,11 +97,11 @@ public interface Registry<T> extends TypeLoader<T> {
default Either<Invalid, T> getByID(String id) {
return getByID(id, map -> {
if(map.isEmpty()) return Either.left(new NoSuchElement("No such value \"" + id + "\""));
if(map.isEmpty()) return left(new NoSuchElement("No such value \"" + id + "\""));
if(map.size() == 1) {
return Either.right(map.values().stream().findFirst().get()); // only one value.
return right(map.values().stream().findFirst().get()); // only one value.
}
return Either.left(new AmbiguousKey("ID \"" + id + "\" is ambiguous; matches: " + map
return left(new AmbiguousKey("ID \"" + id + "\" is ambiguous; matches: " + map
.keySet()
.stream()
.map(RegistryKey::toString)

View File

@@ -4,6 +4,7 @@ import com.dfsek.terra.api.error.Invalid;
import com.dfsek.terra.api.error.InvalidKey;
import com.dfsek.terra.api.util.generic.data.types.Either;
import com.dfsek.terra.api.util.generic.data.types.Maybe;
import static com.dfsek.terra.api.util.function.FunctionUtils.*;
import java.util.Objects;
import java.util.regex.Pattern;
@@ -33,12 +34,12 @@ public final class RegistryKey implements StringIdentifiable, Namespaced {
public static Either<Invalid, RegistryKey> parse(String key) {
if(key.chars().filter(c -> c == ':').count() != 1) {
return Either.left(new InvalidKey("Malformed RegistryKey: " + key));
return left(new InvalidKey("Malformed RegistryKey: " + key));
}
String namespace = key.substring(0, key.indexOf(":"));
String id = key.substring(key.indexOf(":") + 1);
return Either.right(new RegistryKey(namespace, id));
return right(new RegistryKey(namespace, id));
}
public static RegistryKey of(String namespace, String id) {

View File

@@ -2,12 +2,14 @@ package com.dfsek.terra.api.util.function;
import com.dfsek.terra.api.util.generic.data.types.Either;
import com.dfsek.terra.api.util.generic.data.types.Maybe;
import com.dfsek.terra.api.util.generic.data.types.Pair;
import org.jetbrains.annotations.Contract;
import org.jetbrains.annotations.NotNull;
import java.util.Objects;
import java.util.Optional;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Function;
@@ -17,6 +19,30 @@ import java.util.function.Supplier;
public final class FunctionUtils {
private FunctionUtils() { }
public static <T> Function<T, T> identity() {
return Function.identity();
}
public static <T> Maybe<T> just(T t) {
return Maybe.just(t);
}
public static <T> Maybe<T> nothing() {
return Maybe.nothing();
}
public static <L, R> Either<L, R> left(L l) {
return Either.left(l);
}
public static <L, R> Either<L, R> right(R r) {
return Either.right(r);
}
public static <T> Maybe<T> fromOptional(Optional<T> op) {
return Maybe.fromOptional(op);
}
@Contract("_ -> new")
public static <T> @NotNull Function<T, T> lift(@NotNull Consumer<T> c) {
Objects.requireNonNull(c);
@@ -26,6 +52,17 @@ public final class FunctionUtils {
};
}
@Contract("_ -> new")
public static <T, R> @NotNull Function<T, R> lift(@NotNull Supplier<R> c) {
Objects.requireNonNull(c);
return co -> c.get();
}
@Contract("_ -> new")
public static <T, R> @NotNull Function<T, R> lift(@NotNull R c) {
return lift(() -> c);
}
@Contract("_ -> fail")
public static <T extends Throwable, U> @NotNull U throw_(@NotNull T e) throws T {
throw e;

View File

@@ -7,8 +7,6 @@
package com.dfsek.terra.api.util.generic.data.types;
import com.dfsek.terra.api.util.function.FunctionUtils;
import com.dfsek.terra.api.util.generic.control.Monad;
import com.dfsek.terra.api.util.generic.data.BiFunctor;
@@ -20,28 +18,29 @@ import java.util.Objects;
import java.util.Optional;
import java.util.function.Consumer;
import java.util.function.Function;
import static com.dfsek.terra.api.util.function.FunctionUtils.*;
public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L, R, Either<?, ?>> {
static <T> T collapse(Either<T, T> either) {
return either.collect(Function.identity(), Function.identity());
return either.collect(identity(), identity());
}
@SuppressWarnings("unchecked")
static <T, L> Either<L, T> toEither(Optional<T> o, L de) {
return (Either<L, T>) o.map(Either::right).orElseGet(() -> left(de));
return (Either<L, T>) o.map(Either::right).orElseGet(() -> Either.left(de));
}
@NotNull
@Contract("_ -> this")
default Either<L, R> ifLeft(@NotNull Consumer<L> action) {
return mapLeft(FunctionUtils.lift(action));
return mapLeft(lift(action));
}
@NotNull
@Contract("_ -> this")
default Either<L, R> ifRight(@NotNull Consumer<R> action) {
return mapRight(FunctionUtils.lift(action));
return mapRight(lift(action));
}
// Either is a functor in its right parameter.
@@ -52,7 +51,7 @@ public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L
@Override
default <T1> @NotNull Either<?, T1> pure(@NotNull T1 t) {
return right(t);
return Either.right(t);
}
@Override
@@ -64,13 +63,27 @@ public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L
@Override
<R1> @NotNull Either<L, R1> mapRight(@NotNull Function<R, R1> f);
Maybe<L> getLeft();
@Override
@NotNull
default <V, W> Either<V, W> bimap(@NotNull Function<L, V> left, @NotNull Function<R, W> right) {
return (Either<V, W>) BiFunctor.super.bimap(left, right);
}
Maybe<R> getRight();
default Maybe<L> getLeft() {
return collapse(bimap(Maybe::just, lift(Maybe::nothing)));
}
boolean isLeft();
default Maybe<R> getRight() {
return collapse(bimap(lift(Maybe::nothing), Maybe::just));
}
boolean isRight();
default boolean isLeft() {
return collapse(bimap(lift(true), lift(false)));
}
default boolean isRight() {
return collapse(bimap(lift(false), lift(true)));
}
Either<R, L> flip();
@@ -88,7 +101,7 @@ public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L
@SuppressWarnings("Convert2MethodRef")
default <T extends Throwable> R collectThrow(Function<L, T> left) throws T {
return mapLeft(left).collect(l -> FunctionUtils.sneakyThrow(l), Function.identity());
return mapLeft(left).collect(l -> sneakyThrow(l), identity());
}
@NotNull
@@ -122,29 +135,9 @@ public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L
return (Either<L, R1>) this;
}
@Override
public Maybe<L> getLeft() {
return Maybe.just(value);
}
@Override
public Maybe<R> getRight() {
return Maybe.nothing();
}
@Override
public boolean isLeft() {
return true;
}
@Override
public boolean isRight() {
return false;
}
@Override
public Either<R, L> flip() {
return right(value);
return Either.right(value);
}
@Override
@@ -171,29 +164,9 @@ public sealed interface Either<L, R> extends Monad<R, Either<?, ?>>, BiFunctor<L
return new Right<>(f.apply(value));
}
@Override
public Maybe<L> getLeft() {
return Maybe.nothing();
}
@Override
public Maybe<R> getRight() {
return Maybe.just(value);
}
@Override
public boolean isLeft() {
return false;
}
@Override
public boolean isRight() {
return true;
}
@Override
public Either<R, L> flip() {
return left(value);
return Either.left(value);
}
@Override