From 94e30f7ffbafcdd188d09d8c7bf7e4794b650018 Mon Sep 17 00:00:00 2001
From: Linnea Gräf <nea@nea.moe>
Date: Wed, 13 Nov 2024 22:27:28 +0100
Subject: wip

---
 src/main/java/moe/nea/pcj/AppendableError.java    |  21 +++++
 src/main/java/moe/nea/pcj/Codec.java              |   5 +
 src/main/java/moe/nea/pcj/Decode.java             |   5 +
 src/main/java/moe/nea/pcj/Encode.java             |   5 +
 src/main/java/moe/nea/pcj/JsonLikeError.java      |  29 ++++++
 src/main/java/moe/nea/pcj/JsonLikeOperations.java |  28 ++++++
 src/main/java/moe/nea/pcj/ListBuilder.java        |   9 ++
 src/main/java/moe/nea/pcj/ListView.java           |  14 +++
 src/main/java/moe/nea/pcj/Operation.java          |   4 +
 src/main/java/moe/nea/pcj/RecordBuilder.java      |   6 ++
 src/main/java/moe/nea/pcj/RecordView.java         |  10 ++
 src/main/java/moe/nea/pcj/Result.java             | 107 ++++++++++++++++++++++
 src/main/java/moe/nea/pcj/Tuple.java              |  16 ++++
 src/main/java/moe/nea/pcj/Unit.java               |   5 +
 src/main/java/moe/nea/pcj/package-info.java       |   4 +
 15 files changed, 268 insertions(+)
 create mode 100644 src/main/java/moe/nea/pcj/AppendableError.java
 create mode 100644 src/main/java/moe/nea/pcj/Codec.java
 create mode 100644 src/main/java/moe/nea/pcj/Decode.java
 create mode 100644 src/main/java/moe/nea/pcj/Encode.java
 create mode 100644 src/main/java/moe/nea/pcj/JsonLikeError.java
 create mode 100644 src/main/java/moe/nea/pcj/JsonLikeOperations.java
 create mode 100644 src/main/java/moe/nea/pcj/ListBuilder.java
 create mode 100644 src/main/java/moe/nea/pcj/ListView.java
 create mode 100644 src/main/java/moe/nea/pcj/Operation.java
 create mode 100644 src/main/java/moe/nea/pcj/RecordBuilder.java
 create mode 100644 src/main/java/moe/nea/pcj/RecordView.java
 create mode 100644 src/main/java/moe/nea/pcj/Result.java
 create mode 100644 src/main/java/moe/nea/pcj/Tuple.java
 create mode 100644 src/main/java/moe/nea/pcj/Unit.java
 create mode 100644 src/main/java/moe/nea/pcj/package-info.java

(limited to 'src')

diff --git a/src/main/java/moe/nea/pcj/AppendableError.java b/src/main/java/moe/nea/pcj/AppendableError.java
new file mode 100644
index 0000000..6ec48fa
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/AppendableError.java
@@ -0,0 +1,21 @@
+package moe.nea.pcj;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface AppendableError<T extends AppendableError<T>> {
+	/**
+	 * @return an optional Self with getSuppressed containing the argument
+	 */
+	Optional<T> appendError(Object other);
+
+	List<T> getSuppressed();
+
+	static <T> T concatError(T left, T right) {
+		if (left instanceof AppendableError<?> appendable) {
+			var opt = (Optional<T>) appendable.appendError(right);
+			return opt.orElse(left);
+		}
+		return left;
+	}
+}
diff --git a/src/main/java/moe/nea/pcj/Codec.java b/src/main/java/moe/nea/pcj/Codec.java
new file mode 100644
index 0000000..728fbc6
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Codec.java
@@ -0,0 +1,5 @@
+package moe.nea.pcj;
+
+public interface Codec<Typ, Format, DeErr, CoErr> extends Decode<Typ, Format, DeErr>, Encode<Typ, Format, CoErr> {
+
+}
diff --git a/src/main/java/moe/nea/pcj/Decode.java b/src/main/java/moe/nea/pcj/Decode.java
new file mode 100644
index 0000000..a335849
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Decode.java
@@ -0,0 +1,5 @@
+package moe.nea.pcj;
+
+public interface Decode<Typ, Format, Err> {
+	Result<Typ, Err> decode(Format format, Operation<Format> op);
+}
diff --git a/src/main/java/moe/nea/pcj/Encode.java b/src/main/java/moe/nea/pcj/Encode.java
new file mode 100644
index 0000000..0c17097
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Encode.java
@@ -0,0 +1,5 @@
+package moe.nea.pcj;
+
+public interface Encode<Typ, Format, Err> {
+	Result<Format, Err> encode(Typ data, Operation<Format> op);
+}
diff --git a/src/main/java/moe/nea/pcj/JsonLikeError.java b/src/main/java/moe/nea/pcj/JsonLikeError.java
new file mode 100644
index 0000000..6d309ab
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/JsonLikeError.java
@@ -0,0 +1,29 @@
+package moe.nea.pcj;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+
+public abstract class JsonLikeError<Self extends JsonLikeError<?>> implements AppendableError<JsonLikeError<?>> {
+	private final List<JsonLikeError<?>> suppressed = new ArrayList<>();
+
+	protected abstract Self copySelfWithoutSuppressions();
+
+	@Override
+	public List<JsonLikeError<?>> getSuppressed() {
+		return Collections.unmodifiableList(suppressed);
+	}
+
+	@Override
+	public Optional<JsonLikeError<?>> appendError(Object other) {
+		if (other instanceof JsonLikeError<?> jsonLikeOther) {
+			var newSelf = (JsonLikeError<?>) copySelfWithoutSuppressions();
+			newSelf.suppressed.add(jsonLikeOther.copySelfWithoutSuppressions());
+			newSelf.suppressed.addAll(jsonLikeOther.getSuppressed());
+			return Optional.of(newSelf);
+		} else {
+			return Optional.empty();
+		}
+	}
+}
diff --git a/src/main/java/moe/nea/pcj/JsonLikeOperations.java b/src/main/java/moe/nea/pcj/JsonLikeOperations.java
new file mode 100644
index 0000000..2188568
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/JsonLikeOperations.java
@@ -0,0 +1,28 @@
+package moe.nea.pcj;
+
+public interface JsonLikeOperations<Format> extends Operation<Format> {
+
+	Format createNull(Unit value);
+
+	Result<Unit, ? extends JsonLikeError> getNull(Format element);
+
+	Format createNumeric(Number value);
+
+	Result<Number, ? extends JsonLikeError> getInt(Format element);
+
+	Format createString(String value);
+
+	Result<String, ? extends JsonLikeError> getString(Format element);
+
+	Format createBoolean(boolean value);
+
+	Result<Boolean, ? extends JsonLikeError> getBoolean(Format format);
+
+	RecordBuilder<? extends Format, Format> createObject();
+
+	Result<RecordView<? extends Format>, ? extends JsonLikeError> getObject(Format format);
+
+	ListBuilder<? extends Format, Format> createList();
+
+	Result<ListView<? extends Format>, ? extends JsonLikeError> getList(Format format);
+}
diff --git a/src/main/java/moe/nea/pcj/ListBuilder.java b/src/main/java/moe/nea/pcj/ListBuilder.java
new file mode 100644
index 0000000..9f6e9a3
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/ListBuilder.java
@@ -0,0 +1,9 @@
+package moe.nea.pcj;
+
+public interface ListBuilder<Format, ElementFormat> extends ListView<ElementFormat> {
+	Format complete();
+
+	void add(ElementFormat value);
+
+	void set(int index, ElementFormat value);
+}
diff --git a/src/main/java/moe/nea/pcj/ListView.java b/src/main/java/moe/nea/pcj/ListView.java
new file mode 100644
index 0000000..57c229a
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/ListView.java
@@ -0,0 +1,14 @@
+package moe.nea.pcj;
+
+import java.util.Optional;
+
+public interface ListView<Format> {
+	int length();
+
+	default Optional<Format> getSafe(int index) {
+		if (index < 0 || index >= length()) return Optional.empty();
+		return Optional.of(getUnsafe(index));
+	}
+
+	Format getUnsafe(int index);
+}
diff --git a/src/main/java/moe/nea/pcj/Operation.java b/src/main/java/moe/nea/pcj/Operation.java
new file mode 100644
index 0000000..90995ef
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Operation.java
@@ -0,0 +1,4 @@
+package moe.nea.pcj;
+
+public interface Operation<Format> {
+}
diff --git a/src/main/java/moe/nea/pcj/RecordBuilder.java b/src/main/java/moe/nea/pcj/RecordBuilder.java
new file mode 100644
index 0000000..c28be7b
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/RecordBuilder.java
@@ -0,0 +1,6 @@
+package moe.nea.pcj;
+
+public interface RecordBuilder<Format, ElementFormat> extends RecordView<ElementFormat> {
+	void add(String key, ElementFormat value); // TODO
+	Format complete();
+}
diff --git a/src/main/java/moe/nea/pcj/RecordView.java b/src/main/java/moe/nea/pcj/RecordView.java
new file mode 100644
index 0000000..84057ba
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/RecordView.java
@@ -0,0 +1,10 @@
+package moe.nea.pcj;
+
+import java.util.Collection;
+import java.util.Optional;
+
+public interface RecordView<Format> {
+	Collection<Format> getKeys();
+
+	Optional<Format> get(String key);
+}
diff --git a/src/main/java/moe/nea/pcj/Result.java b/src/main/java/moe/nea/pcj/Result.java
new file mode 100644
index 0000000..8bec96a
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Result.java
@@ -0,0 +1,107 @@
+package moe.nea.pcj;
+
+import org.jspecify.annotations.Nullable;
+
+import java.util.Optional;
+import java.util.function.Function;
+
+public sealed interface Result<Good, Bad> permits Result.Ok, Result.Fail {
+	default boolean isOk() {
+		return error().isEmpty();
+	}
+
+	Optional<Good> value();
+
+	Optional<Good> partial();
+
+	default Optional<Good> valueOrPartial() {
+		return value().or(this::partial);
+	}
+
+	Optional<Bad> error();
+
+	default <Next> Result<Next, Bad> map(Function<Good, Next> mapper) {
+		return flatMap(mapper.andThen(Result::ok));
+	}
+
+	default <Next> Result<Next, Bad> flatMap(Function<Good, Result<Next, Bad>> mapper) {
+		return flatMapBoth(mapper, Result::fail);
+	}
+
+	<NextGood> Result<NextGood, Bad> flatMapBoth(
+			Function<Good, Result<NextGood, Bad>> mapGood,
+			Function<Bad, Result<NextGood, Bad>> mapBad);
+
+	Result<Good, Bad> appendError(Bad error);
+
+	record Ok<Good, Bad>(Good okValue) implements Result<Good, Bad> {
+		@Override
+		public Result<Good, Bad> appendError(Bad error) {
+			return Result.partial(okValue, error);
+		}
+
+		@Override
+		public Optional<Good> partial() {
+			return Optional.empty();
+		}
+
+		@Override
+		public Optional<Good> value() {
+			return Optional.of(okValue);
+		}
+
+		@Override
+		public Optional<Bad> error() {
+			return Optional.empty();
+		}
+
+		@Override
+		public <NextGood> Result<NextGood, Bad> flatMapBoth(Function<Good, Result<NextGood, Bad>> mapGood, Function<Bad, Result<NextGood, Bad>> mapBad) {
+			return mapGood.apply(okValue);
+		}
+	}
+
+	record Fail<Good, Bad>(@Nullable Good partialValue, Bad badValue) implements Result<Good, Bad> {
+
+		@Override
+		public Optional<Good> value() {
+			return Optional.empty();
+		}
+
+		@Override
+		public Optional<Good> partial() {
+			return Optional.ofNullable(partialValue);
+		}
+
+		@Override
+		public Optional<Bad> error() {
+			return Optional.of(badValue);
+		}
+
+		@Override
+		public <NextGood> Result<NextGood, Bad> flatMapBoth(Function<Good, Result<NextGood, Bad>> mapGood, Function<Bad, Result<NextGood, Bad>> mapBad) {
+			if (partialValue != null) {
+				var nextPartial = mapGood.apply(partialValue);
+				return nextPartial.appendError(badValue);
+			}
+			return mapBad.apply(badValue);
+		}
+
+		@Override
+		public Result<Good, Bad> appendError(Bad error) {
+			return Result.partial(partialValue, AppendableError.concatError(badValue, error));
+		}
+	}
+
+	static <Good, Bad> Result<Good, Bad> ok(Good value) {
+		return new Ok<>(value);
+	}
+
+	static <Good, Bad> Result.Fail<Good, Bad> fail(Bad error) {
+		return new Fail<>(null, error);
+	}
+
+	static <Good, Bad> Result.Fail<Good, Bad> partial(@Nullable Good partial, Bad error) {
+		return new Fail<>(partial, error);
+	}
+}
diff --git a/src/main/java/moe/nea/pcj/Tuple.java b/src/main/java/moe/nea/pcj/Tuple.java
new file mode 100644
index 0000000..baaceef
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Tuple.java
@@ -0,0 +1,16 @@
+package moe.nea.pcj;
+
+public interface Tuple {
+	record Tuple2<A, B>(A first, B second) implements Tuple {}
+
+	record Tuple3<A, B, C>(A first, B second, C third) implements Tuple {}
+
+	record Tuple4<A, B, C, D>(A first, B second, C third, D fourth) implements Tuple {}
+
+	record Tuple5<A, B, C, D, E>(A first, B second, C third, D fourth, E fifth) implements Tuple {}
+
+	record Tuple6<A, B, C, D, E, F>(A first, B second, C third, D fourth, E fifth, F sixth) implements Tuple {}
+
+	record Tuple7<A, B, C, D, E, F, G>(A first, B second, C third, D fourth, E fifth, F sixth,
+	                                   G seventh) implements Tuple {}
+}
diff --git a/src/main/java/moe/nea/pcj/Unit.java b/src/main/java/moe/nea/pcj/Unit.java
new file mode 100644
index 0000000..435d763
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/Unit.java
@@ -0,0 +1,5 @@
+package moe.nea.pcj;
+
+public enum Unit {
+	INSTANCE;
+}
diff --git a/src/main/java/moe/nea/pcj/package-info.java b/src/main/java/moe/nea/pcj/package-info.java
new file mode 100644
index 0000000..8adfc56
--- /dev/null
+++ b/src/main/java/moe/nea/pcj/package-info.java
@@ -0,0 +1,4 @@
+@NullMarked
+package moe.nea.pcj;
+
+import org.jspecify.annotations.NullMarked;
\ No newline at end of file
-- 
cgit