Support constructed struct type as case in when expression

1 files changed, 18 insertions, 2 deletions

diff --git a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
index 3ca2b5ae..3695a255 100644
--- a/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/shedlang/compiler/typechecker/TypeChecker.java
@@ -2118,11 +2118,27 @@ public class TypeChecker {
         TypeCheckerContext context
     ) {
         var typedCaseType = typeCheckTypeLevelExpression(
-            TypeSets.STRUCT_META_TYPE,
+            TypeSets.META_TYPE,
             untyped.caseType(),
             context
         );
 
+        var variant = switch (typedCaseType.value()) {
+            case ConstructedType<?> constructedType when constructedType.genericType() instanceof StructType ->
+                SumVariant.constructedStruct((ConstructedType<StructType>) constructedType);
+
+            case StructType structType ->
+                SumVariant.struct(structType);
+
+            default ->
+                throw new UnexpectedTypeError(
+                    // TODO: somehow update TypeSets.STRUCT_META_TYPE to allow constructed struct types
+                    TypeSets.STRUCT_META_TYPE,
+                    typedCaseType.value(),
+                    untyped.caseType().source()
+                );
+        };
+
         var declaredVariables = DeclaredVariables.forFunctionStatements(
             untyped.body().statements(),
             P.vector()
@@ -2142,7 +2158,7 @@ public class TypeChecker {
         context = context.exit();
 
         return context.toResult(new TypedWhenCaseNode(
-            SumVariant.struct(typedCaseType.value()),
+            variant,
             typedBody,
             untyped.source()
         ));