WIP on wildcard types

Author: stanhebben

CodeModel/src/main/java/org/openzen/zenscript/codemodel/compilation/TypeBuilder.java

@@ -27,6 +27,10 @@ public interface TypeBuilder {
 
 	FunctionTypeID functionOf(FunctionHeader header);
 
+	WildcardInTypeID wildcardIn(TypeID type);
+
+	WildcardOutTypeID wildcardOut(TypeID type);
+
 	TypeID resultOf(TypeID type, TypeID thrownType);
 
 	GenericMapTypeBuilder withGeneric(TypeParameter... parameters);

CodeModel/src/main/java/org/openzen/zenscript/codemodel/compilation/impl/AbstractTypeBuilder.java

@@ -60,6 +60,16 @@ public TypeID resultOf(TypeID type, TypeID thrownType) {
 		return DefinitionTypeID.create(ResultTypeSymbol.INSTANCE, type, thrownType);
 	}
 
+	@Override
+	public WildcardInTypeID wildcardIn(TypeID type) {
+		return new WildcardInTypeID(type);
+	}
+
+	@Override
+	public WildcardOutTypeID wildcardOut(TypeID type) {
+		return new WildcardOutTypeID(type);
+	}
+
 	@Override
 	public GenericMapTypeBuilder withGeneric(TypeParameter... parameters) {
 		return new Generic() {

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/InferenceBlockingTypeParameterVisitor.java

@@ -250,6 +250,16 @@ public Boolean visitOptional(OptionalTypeID type) {
 		return blocking;
 	}
 
+	@Override
+	public Boolean visitWildcardIn(WildcardInTypeID type) {
+		return true;
+	}
+
+	@Override
+	public Boolean visitWildcardOut(WildcardOutTypeID type) {
+		return true; // TODO: or should we allow it to infer to be the lower bound?
+	}
+
 	@Override
 	public Boolean visitInvalid(InvalidTypeID type) {
 		Optional<Boolean> knownResult = getKnownResult(type);

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/TypeMatcher.java

@@ -143,6 +143,26 @@ public Boolean visitOptional(Matching context, OptionalTypeID type) {
 		}
 	}
 
+	@Override
+	public Boolean visitWildcardIn(Matching context, WildcardInTypeID type) throws RuntimeException {
+		if (context.type instanceof WildcardInTypeID) {
+			WildcardInTypeID wildcardIn = (WildcardInTypeID) context.type;
+			return match(context, wildcardIn.upperBound, type.upperBound);
+		} else {
+			return false;
+		}
+	}
+
+	@Override
+	public Boolean visitWildcardOut(Matching context, WildcardOutTypeID type) throws RuntimeException {
+		if (context.type instanceof WildcardOutTypeID) {
+			WildcardOutTypeID wildcardOut = (WildcardOutTypeID) context.type;
+			return match(context, wildcardOut.lowerBound, type.lowerBound);
+		} else {
+			return false;
+		}
+	}
+
 	private boolean match(Matching context, TypeID type, TypeID pattern) {
 		return pattern.accept(context.withType(type), this);
 	}

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/TypeVisitor.java

@@ -21,6 +21,10 @@ public interface TypeVisitor<T> {
 
 	T visitOptional(OptionalTypeID type);
 
+	T visitWildcardIn(WildcardInTypeID type);
+
+	T visitWildcardOut(WildcardOutTypeID type);
+
 	default T visitInvalid(InvalidTypeID type) {
 		throw new UnsupportedOperationException("Invalid type @ " + type.position +  ": " + type.error.description);
 	}

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/TypeVisitorWithContext.java

@@ -21,6 +21,10 @@ public interface TypeVisitorWithContext<C, R, E extends Exception> {
 
 	R visitOptional(C context, OptionalTypeID type) throws E;
 
+	R visitWildcardIn(C context, WildcardInTypeID type) throws E;
+
+	R visitWildcardOut(C context, WildcardOutTypeID type) throws E;
+
 	default R visitInvalid(C context, InvalidTypeID type) throws E {
 		throw new RuntimeException("Invalid type: " + type.error.description);
 	}

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/WildcardInTypeID.java

@@ -0,0 +1,53 @@
+package org.openzen.zenscript.codemodel.type;
+
+import org.openzen.zenscript.codemodel.GenericMapper;
+import org.openzen.zenscript.codemodel.compilation.ResolvingType;
+import org.openzen.zenscript.codemodel.generic.TypeParameter;
+import org.openzen.zenscript.codemodel.type.member.MemberSet;
+
+import java.util.List;
+
+public class WildcardInTypeID implements TypeID {
+	public final TypeID upperBound;
+
+	public WildcardInTypeID(TypeID upperBound) {
+		this.upperBound = upperBound;
+	}
+
+	@Override
+	public TypeID instance(GenericMapper mapper) {
+		TypeID mappedUpperBound = upperBound.instance(mapper);
+		return mappedUpperBound == upperBound ? this : new WildcardInTypeID(mappedUpperBound);
+	}
+
+	@Override
+	public boolean hasDefaultValue() {
+		return false;
+	}
+
+	@Override
+	public void extractTypeParameters(List<TypeParameter> typeParameters) {
+		upperBound.extractTypeParameters(typeParameters);
+	}
+
+	@Override
+	public <R> R accept(TypeVisitor<R> visitor) {
+		return visitor.visitWildcardIn(this);
+	}
+
+	@Override
+	public <C, R, E extends Exception> R accept(C context, TypeVisitorWithContext<C, R, E> visitor) throws E {
+		return visitor.visitWildcardIn(context, this);
+	}
+
+	@Override
+	public boolean isValueType() {
+		return false;
+	}
+
+	@Override
+	public ResolvingType resolve() {
+		// No members to inherit, since there is no lower bound...
+		return MemberSet.create(this).build();
+	}
+}

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/WildcardOutTypeID.java

@@ -0,0 +1,53 @@
+package org.openzen.zenscript.codemodel.type;
+
+import org.openzen.zenscript.codemodel.GenericMapper;
+import org.openzen.zenscript.codemodel.compilation.ResolvingType;
+import org.openzen.zenscript.codemodel.generic.TypeParameter;
+import org.openzen.zenscript.codemodel.type.member.MemberSet;
+
+import java.util.List;
+
+public class WildcardOutTypeID implements TypeID {
+	public final TypeID lowerBound;
+
+	public WildcardOutTypeID(TypeID lowerBound) {
+		this.lowerBound = lowerBound;
+	}
+
+	@Override
+	public TypeID instance(GenericMapper mapper) {
+		TypeID mappedLowerBound = lowerBound.instance(mapper);
+		return mappedLowerBound == lowerBound ? this : new WildcardOutTypeID(mappedLowerBound);
+	}
+
+	@Override
+	public boolean hasDefaultValue() {
+		return false;
+	}
+
+	@Override
+	public void extractTypeParameters(List<TypeParameter> typeParameters) {
+		lowerBound.extractTypeParameters(typeParameters);
+	}
+
+	@Override
+	public <R> R accept(TypeVisitor<R> visitor) {
+		return visitor.visitWildcardOut(this);
+	}
+
+	@Override
+	public <C, R, E extends Exception> R accept(C context, TypeVisitorWithContext<C, R, E> visitor) throws E {
+		return visitor.visitWildcardOut(context, this);
+	}
+
+	@Override
+	public boolean isValueType() {
+		return false;
+	}
+
+	@Override
+	public ResolvingType resolve() {
+		// No members to inherit, since there is no lower bound...
+		return MemberSet.create(this).build();
+	}
+}

JavaIntegration/src/main/java/org/openzen/zencode/java/module/JavaNativeTypeMembers.java

@@ -66,7 +66,6 @@ public Optional<StaticCallable> findSuffixConstructor(String suffix) {
 	@Override
 	public Optional<InstanceCallableMethod> findCaster(TypeID toType) {
 		return template.getMethod(MethodID.caster(toType)).stream().findFirst().map(c -> mapper.map(type, c));
-
 	}
 
 	@Override

Parser/src/main/java/org/openzen/zenscript/lexer/ZSTokenType.java

@@ -140,6 +140,7 @@ public enum ZSTokenType implements TokenType {
 	K_DEFAULT(true, "default"),
 
 	K_IN(true, "in"),
+	K_OUT(true, "out"),
 	K_IS(true, "is"),
 	K_AS(true, "as"),
 	K_MATCH(true, "match"),