Merge variable declaration and definition

6 files changed, 23 insertions, 78 deletions

diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeChecker.java b/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeChecker.java
index 98b29a9..abc4bec 100644
--- a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeChecker.java
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeChecker.java
@@ -30,7 +30,7 @@ public class TypeChecker {
 
             var importedNamespaceFields = context.namespaceFields(importedNamespace);
             for (var importedName : untypedImport.importedNames()) {
-                namespaceContext.define(importedName, importedNamespaceFields.get(importedName));
+                namespaceContext.declare(importedName, importedNamespaceFields.get(importedName));
             }
         }
 
@@ -92,10 +92,8 @@ public class TypeChecker {
         TypeCheckerNamespaceContext context
     ) {
         var nativeType = new SimpleNativeType(context.namespaceName(), untyped.name());
-        // TODO: tidy up declare vs define
-        context.declare(untyped.name());
         var metaType = new TypeLevelValueType(nativeType);
-        context.define(untyped.name(), metaType);
+        context.declare(untyped.name(), metaType);
         return metaType;
     }
 
@@ -117,10 +115,8 @@ public class TypeChecker {
         TypeCheckerNamespaceContext context
     ) {
         var structType = new StructType(context.namespaceName(), untyped.name());
-        // TODO: tidy up declare vs define
-        context.declare(untyped.name());
         var metaType = new TypeLevelValueType(structType);
-        context.define(untyped.name(), metaType);
+        context.declare(untyped.name(), metaType);
         return metaType;
     }
 
@@ -173,10 +169,8 @@ public class TypeChecker {
         TypeCheckerNamespaceContext context
     ) {
         var sumType = new SumType(context.namespaceName(), untyped.name());
-        // TODO: tidy up declare vs define
-        context.declare(untyped.name());
         var metaType = new TypeLevelValueType(sumType);
-        context.define(untyped.name(), metaType);
+        context.declare(untyped.name(), metaType);
         return metaType;
     }
 
@@ -284,17 +278,9 @@ public class TypeChecker {
         Source source,
         TypeCheckerNamespaceContext context
     ) {
-        var variable = context.lookup(name)
+        var type = context.lookupType(name)
             .orElseThrow(() -> new UndeclaredVariableError(name, source));
 
-        var type = switch (variable) {
-            case Variable.Declared declared ->
-                throw new UndefinedVariableError(name, source);
-
-            case Variable.Defined defined ->
-                defined.type();
-        };
-
         // TODO: handle not a type-level value
         if (!(type instanceof TypeLevelValueType(TypeLevelValue value))) {
             throw new UnexpectedTypeError(new TypeSet.MetaType(), type, source);
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerNamespaceContext.java b/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerNamespaceContext.java
index 6366a12..69827a8 100644
--- a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerNamespaceContext.java
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerNamespaceContext.java
@@ -3,10 +3,10 @@ package org.zwobble.hobgoblin.compiler.typechecker;
 import org.zwobble.hobgoblin.compiler.types.*;
 import org.zwobble.hobgoblin.compiler.util.ManyToMany;
 
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
-import java.util.stream.Collectors;
 
 public class TypeCheckerNamespaceContext {
     public static TypeCheckerNamespaceContext initial(
@@ -15,23 +15,22 @@ public class TypeCheckerNamespaceContext {
         Map<StructType, List<Field>> fieldsOf,
         ManyToMany<SumType, Type> variants
     ) {
-        var variables = nativeTypes.entrySet().stream()
-            .collect(Collectors.toMap(
-                entry -> entry.getKey(),
-                entry -> Variable.defined(entry.getValue())
-            ));
-
-        return new TypeCheckerNamespaceContext(namespaceName, variables, fieldsOf, variants);
+        return new TypeCheckerNamespaceContext(
+            namespaceName,
+            new HashMap<>(nativeTypes),
+            fieldsOf,
+            variants
+        );
     }
 
     private final NamespaceName namespaceName;
-    private final Map<String, Variable> variables;
+    private final Map<String, Type> variables;
     private final Map<StructType, List<Field>> fieldsOf;
     private final ManyToMany<SumType, Type> variants;
 
     private TypeCheckerNamespaceContext(
         NamespaceName namespaceName,
-        Map<String, Variable> variables,
+        Map<String, Type> variables,
         Map<StructType, List<Field>> fieldsOf,
         ManyToMany<SumType, Type> variants
     ) {
@@ -45,17 +44,12 @@ public class TypeCheckerNamespaceContext {
         return this.namespaceName;
     }
 
-    public void declare(String name) {
+    public void declare(String name, Type type) {
         // TODO: Check variable is not already declared.
-        this.variables.put(name, new Variable.Declared());
-    }
-
-    public void define(String name, Type type) {
-        // TODO: Check variable is not already defined.
-        this.variables.put(name, new Variable.Defined(type));
+        this.variables.put(name, type);
     }
 
-    public Optional<Variable> lookup(String name) {
+    public Optional<Type> lookupType(String name) {
         return Optional.ofNullable(this.variables.get(name));
     }
 
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/Variable.java b/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/Variable.java
deleted file mode 100644
index e80283f..0000000
--- a/src/main/java/org/zwobble/hobgoblin/compiler/typechecker/Variable.java
+++ /dev/null
@@ -1,15 +0,0 @@
-package org.zwobble.hobgoblin.compiler.typechecker;
-
-import org.zwobble.hobgoblin.compiler.types.Type;
-
-public sealed interface Variable {
-    public static Variable defined(Type type) {
-        return new Defined(type);
-    }
-
-    record Declared() implements Variable {
-    }
-
-    record Defined(Type type) implements Variable {
-    }
-}
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerConstructedTypeTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerConstructedTypeTests.java
index 1f3e5ff..ef55465 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerConstructedTypeTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerConstructedTypeTests.java
@@ -18,13 +18,11 @@ public class TypeCheckerConstructedTypeTests {
             List.of(UntypedArb.typeLevelReference("Int32"))
         );
         var context = TypeCheckerContextArb.namespaceContext();
-        context.declare("List");
         var listType = SimpleNativeType.builtin("List");
         var listTypeConstructor = new TypeConstructor<>(List.of(new TypeParam("T")), listType);
-        context.define("List", new TypeLevelValueType(listTypeConstructor));
-        context.declare("Int32");
+        context.declare("List", new TypeLevelValueType(listTypeConstructor));
         var int32Type = SimpleNativeType.builtin("Int32");
-        context.define("Int32", new TypeLevelValueType(int32Type));
+        context.declare("Int32", new TypeLevelValueType(int32Type));
 
         var typed = TypeChecker.typeCheckTypeLevelExpression(untyped, context);
 
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerSumDefinitionTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerSumDefinitionTests.java
index c93868b..60c2b9a 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerSumDefinitionTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerSumDefinitionTests.java
@@ -48,10 +48,8 @@ public class TypeCheckerSumDefinitionTests {
         var globalContext = TypeCheckerGlobalContext.initial();
         var namespaceContext = globalContext
             .enterNamespace(NamespaceName.of("a", "b"));
-        namespaceContext.declare(rectangleType.name());
-        namespaceContext.define(rectangleType.name(), new TypeLevelValueType(rectangleType));
-        namespaceContext.declare(triangleType.name());
-        namespaceContext.define(triangleType.name(), new TypeLevelValueType(triangleType));
+        namespaceContext.declare(rectangleType.name(), new TypeLevelValueType(rectangleType));
+        namespaceContext.declare(triangleType.name(), new TypeLevelValueType(triangleType));
 
         var typed = typeCheckNamespaceStatement(untyped, namespaceContext);
 
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerTypeLevelReferenceTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerTypeLevelReferenceTests.java
index ef90d3e..e633c94 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerTypeLevelReferenceTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/typechecker/TypeCheckerTypeLevelReferenceTests.java
@@ -26,26 +26,11 @@ public class TypeCheckerTypeLevelReferenceTests {
     }
 
     @Test
-    public void whenNameIsUndefinedThenErrorIsThrown() {
-        var untyped = UntypedArb.typeLevelReference("X");
-        var context = TypeCheckerContextArb.namespaceContext();
-        context.declare("X");
-
-        var error = assertThrows(
-            UndefinedVariableError.class,
-            () -> TypeChecker.typeCheckTypeLevelExpression(untyped, context)
-        );
-
-        assertThat(error.variableName(), equalTo("X"));
-    }
-
-    @Test
     public void whenVariableIsNotTypeLevelValueThenErrorIsThrown() {
         var untyped = UntypedArb.typeLevelReference("X");
         var context = TypeCheckerContextArb.namespaceContext();
-        context.declare("X");
         var nativeType = SimpleNativeType.builtin("Int");
-        context.define("X", nativeType);
+        context.declare("X", nativeType);
 
         var error = assertThrows(
             UnexpectedTypeError.class,
@@ -60,9 +45,8 @@ public class TypeCheckerTypeLevelReferenceTests {
     public void whenNameIsMetaTypeThenValueIsType() {
         var untyped = UntypedArb.typeLevelReference("X");
         var context = TypeCheckerContextArb.namespaceContext();
-        context.declare("X");
         var nativeType = SimpleNativeType.builtin("Int");
-        context.define("X", new TypeLevelValueType(nativeType));
+        context.declare("X", new TypeLevelValueType(nativeType));
 
         var typed = TypeChecker.typeCheckTypeLevelExpression(untyped, context);