Support constructed struct type constructors

4 files changed, 92 insertions, 12 deletions

diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedArgsNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedArgsNode.java
index 202cb888..177982ea 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedArgsNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedArgsNode.java
@@ -27,6 +27,13 @@ public record UntypedArgsNode(
             return new UntypedArgsNode(positional, named, Sources.NULL);
         }
 
+        public Builder addPositionalArg(UntypedExpressionNode arg) {
+            return new Builder(
+                this.positional.plus(arg),
+                this.named
+            );
+        }
+
         public Builder addNamedArg(UntypedNamedArgNode arg) {
             return new Builder(
                 this.positional,
diff --git a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedCallNode.java b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedCallNode.java
index e9624263..73219c47 100644
--- a/src/main/java/org/shedlang/compiler/ast/untyped/UntypedCallNode.java
+++ b/src/main/java/org/shedlang/compiler/ast/untyped/UntypedCallNode.java
@@ -47,6 +47,24 @@ public record UntypedCallNode(
             );
         }
 
+        public Builder withTypeLevelArgs(List<UntypedTypeLevelExpressionNode> typeLevelArgs) {
+            return new Builder(
+                this.receiver,
+                Optional.of(typeLevelArgs),
+                this.args,
+                this.hasEffects
+            );
+        }
+
+        public Builder addPositionalArg(UntypedExpressionNode arg) {
+            return new Builder(
+                this.receiver,
+                this.typeLevelArgs,
+                this.args.addPositionalArg(arg),
+                this.hasEffects
+            );
+        }
+
         public Builder addNamedArg(UntypedNamedArgNode arg) {
             return new Builder(
                 this.receiver,
diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
index 2eef55f1..ac3fde79 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
@@ -326,7 +326,28 @@ public class TypeChecker {
         var typedReceiver = receiverResult.value();
         context = receiverResult.context();
 
-        var receiverType = receiverTypeToFunctionType(typedReceiver, context);
+        var contextForReceiver = context;
+        var receiverType = untyped.typeLevelArgs()
+            .map(untypedTypeLevelArgNodes -> {
+                var typeLevelArgs = untypedTypeLevelArgNodes.stream()
+                    .map(argNode -> typeCheckTypeExpression(argNode, contextForReceiver).value())
+                    .toList();
+
+                if (
+                    typedReceiver.type() instanceof TypeLevelValueType initialReceiverType &&
+                    initialReceiverType.value() instanceof TypeConstructor<?> typeConstructor
+                ) {
+                    // TODO: check args
+                    return receiverTypeToFunctionType(
+                        Types.metaType(Types.constructedType(typeConstructor, typeLevelArgs)),
+                        typedReceiver.source(),
+                        contextForReceiver
+                    );
+                } else {
+                    throw new IllegalArgumentException("TODO");
+                }
+            })
+            .orElseGet(() -> receiverTypeToFunctionType(typedReceiver, contextForReceiver));
 
         var argsResult = typeCheckArgs(untyped.args(), context, receiverType);
         var typedArgs = argsResult.value();
@@ -381,20 +402,20 @@ public class TypeChecker {
 
         if (
             receiverType instanceof TypeLevelValueType typeLevelValueType &&
-                typeLevelValueType.value() instanceof StructType structType
+            typeLevelValueType.value() instanceof StructType structType
         ) {
             var structTypeInfo = context.structTypeInfo(structType, receiverSource);
+            return receiverStructTypeInfoToFunctionType(structType, structTypeInfo);
+        }
 
-            var namedParams = structTypeInfo.fields().stream()
-                .map(field -> new NamedParam(field.name(), field.type()))
-                .toList();
-
-            return new FunctionType(
-                List.of(),
-                namedParams,
-                Effects.NONE,
-                structType
-            );
+        if (
+            receiverType instanceof TypeLevelValueType typeLevelValueType &&
+            typeLevelValueType.value() instanceof ConstructedType<?> constructedType &&
+            constructedType.genericType() instanceof StructType structType
+        ) {
+            // TODO: make specific constructed types to avoid generic casting?
+            var structTypeInfo = context.structTypeInfo((ConstructedType<StructType>) constructedType, receiverSource);
+            return receiverStructTypeInfoToFunctionType(constructedType, structTypeInfo);
         }
 
         throw new UnexpectedTypeError(
@@ -404,6 +425,22 @@ public class TypeChecker {
         );
     }
 
+    private static FunctionType receiverStructTypeInfoToFunctionType(
+        Type structType,
+        StructTypeInfo structTypeInfo
+    ) {
+        var namedParams = structTypeInfo.fields().stream()
+            .map(field -> new NamedParam(field.name(), field.type()))
+            .toList();
+
+        return new FunctionType(
+            List.of(),
+            namedParams,
+            Effects.NONE,
+            structType
+        );
+    }
+
     private static TypeCheckerResult<TypedConditionalBranchNode> typeCheckConditionalBranch(
         UntypedConditionalBranchNode conditionalBranch,
         TypeCheckerContext context
diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeCheckerContext.java b/src/main/java/org/shedlang/compiler/typechecker/TypeCheckerContext.java
index d783aafe..dcaa9226 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeCheckerContext.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeCheckerContext.java
@@ -443,6 +443,24 @@ public class TypeCheckerContext {
         );
     }
 
+    public StructTypeInfo structTypeInfo(ConstructedType<StructType> type, Source source) {
+        var typeInfo = this.typeInfos.structTypeInfo(type.genericType())
+            .orElseThrow(() -> new MissingStructTypeInfoError(type.genericType(), source));
+
+        var typeSubstitutionMap = type.typeSubstitutionMap();
+
+        var fieldsInfoBuilder = FieldsInfo.builder();
+
+        for (var field : typeInfo.fields()) {
+            fieldsInfoBuilder = fieldsInfoBuilder.addField(
+                field.name(),
+                TypeSubstitution.substitute(field.type(), typeSubstitutionMap)
+            );
+        }
+
+        return new StructTypeInfo(fieldsInfoBuilder.build());
+    }
+
     public StructTypeInfo structTypeInfo(StructType type, Source source) {
         return this.typeInfos.structTypeInfo(type)
             .orElseThrow(() -> new MissingStructTypeInfoError(type, source));