Introduce Type interface

14 files changed, 139 insertions, 115 deletions

diff --git a/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java b/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
index 2544c4a..10c550b 100644
--- a/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/BackendEvalTests.java
@@ -2,6 +2,7 @@ package org.zwobble.couscous.tests;
 
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.values.IntegerValue;
 import org.zwobble.couscous.values.PrimitiveValue;
 import org.zwobble.couscous.values.StringValue;
@@ -42,8 +43,8 @@ public abstract class BackendEvalTests {
         assertEquals(
             value(false),
             evalExpression(same(
-                constructorCall(TypeName.of("java.lang.Object"), Collections.emptyList()),
-                constructorCall(TypeName.of("java.lang.Object"), Collections.emptyList()))));
+                constructorCall(ScalarType.of("java.lang.Object"), Collections.emptyList()),
+                constructorCall(ScalarType.of("java.lang.Object"), Collections.emptyList()))));
     }
     
     @Test
@@ -228,7 +229,7 @@ public abstract class BackendEvalTests {
 
     @Test
     public void staticConstructorIsExecutedOnReference() {
-        TypeName type = TypeName.of("com.example.Example");
+        ScalarType type = ScalarType.of("com.example.Example");
         ClassNode classNode = ClassNode.builder(type)
             .staticField("value", IntegerValue.REF)
             .staticConstructor(list(
diff --git a/src/test/java/org/zwobble/couscous/tests/CompilerTests.java b/src/test/java/org/zwobble/couscous/tests/CompilerTests.java
index 059130c..629f288 100644
--- a/src/test/java/org/zwobble/couscous/tests/CompilerTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/CompilerTests.java
@@ -1,7 +1,7 @@
 package org.zwobble.couscous.tests;
 
 import org.junit.Test;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.values.BooleanValue;
 import org.zwobble.couscous.values.IntegerValue;
 import org.zwobble.couscous.values.PrimitiveValue;
@@ -56,7 +56,7 @@ public abstract class CompilerTests {
             value(720),
             execTestProgram(
                 "recursive-factorial",
-                TypeName.of("com.example.RecursiveFactorial"),
+                ScalarType.of("com.example.RecursiveFactorial"),
                 "factorial",
                 list(value(6)),
                 IntegerValue.REF));
@@ -68,7 +68,7 @@ public abstract class CompilerTests {
             value(720),
             execTestProgram(
                 "while-factorial",
-                TypeName.of("com.example.WhileFactorial"),
+                ScalarType.of("com.example.WhileFactorial"),
                 "factorial",
                 list(value(6)),
                 IntegerValue.REF));
@@ -80,7 +80,7 @@ public abstract class CompilerTests {
             value(720),
             execTestProgram(
                 "for-factorial",
-                TypeName.of("com.example.ForFactorial"),
+                ScalarType.of("com.example.ForFactorial"),
                 "factorial",
                 list(value(6)),
                 IntegerValue.REF));
@@ -92,7 +92,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "static-nested-class",
-                TypeName.of("com.example.StaticNestedClass"),
+                ScalarType.of("com.example.StaticNestedClass"),
                 "value",
                 list(),
                 IntegerValue.REF));
@@ -104,7 +104,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "inner-class",
-                TypeName.of("com.example.InnerClass"),
+                ScalarType.of("com.example.InnerClass"),
                 "run",
                 list(),
                 IntegerValue.REF));
@@ -116,7 +116,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "inner-class-with-constructor-args",
-                TypeName.of("com.example.InnerClass"),
+                ScalarType.of("com.example.InnerClass"),
                 "run",
                 list(),
                 IntegerValue.REF));
@@ -128,7 +128,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "implement-user-interface",
-                TypeName.of("com.example.ConstantIntSupplier"),
+                ScalarType.of("com.example.ConstantIntSupplier"),
                 "value",
                 list(),
                 IntegerValue.REF));
@@ -140,7 +140,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "anonymous-class",
-                TypeName.of("com.example.AnonymousClass"),
+                ScalarType.of("com.example.AnonymousClass"),
                 "value",
                 list(),
                 IntegerValue.REF));
@@ -152,7 +152,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "anonymous-class-capture",
-                TypeName.of("com.example.AnonymousClass"),
+                ScalarType.of("com.example.AnonymousClass"),
                 "value",
                 list(value(42)),
                 IntegerValue.REF));
@@ -164,7 +164,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "lambda",
-                TypeName.of("com.example.Lambda"),
+                ScalarType.of("com.example.Lambda"),
                 "value",
                 list(),
                 IntegerValue.REF));
@@ -176,7 +176,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "lambda-capture",
-                TypeName.of("com.example.Lambda"),
+                ScalarType.of("com.example.Lambda"),
                 "value",
                 list(value(2)),
                 IntegerValue.REF));
@@ -188,7 +188,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "lambda-this-capture",
-                TypeName.of("com.example.Lambda"),
+                ScalarType.of("com.example.Lambda"),
                 "value",
                 list(value(2)),
                 IntegerValue.REF));
@@ -200,7 +200,7 @@ public abstract class CompilerTests {
             value("Hello"),
             execTestProgram(
                 "generic-interface",
-                TypeName.of("com.example.GenericInterface"),
+                ScalarType.of("com.example.GenericInterface"),
                 "value",
                 list(),
                 StringValue.REF));
@@ -212,7 +212,7 @@ public abstract class CompilerTests {
             value(42),
             execTestProgram(
                 "static-method-overloads",
-                TypeName.of("com.example.StaticMethodOverloads"),
+                ScalarType.of("com.example.StaticMethodOverloads"),
                 "value",
                 list(),
                 IntegerValue.REF));
@@ -237,10 +237,10 @@ public abstract class CompilerTests {
 
     private PrimitiveValue execTestProgram(
         String directoryName,
-        TypeName type,
+        ScalarType type,
         String methodName,
         List<PrimitiveValue> arguments,
-        TypeName returnType) throws IOException, InterruptedException {
+        ScalarType returnType) throws IOException, InterruptedException {
 
         Path path = pathForResource(
             "/java/" + directoryName + "/" + type.getQualifiedName().replace(".", "/") + ".java");
@@ -255,10 +255,10 @@ public abstract class CompilerTests {
 
     protected abstract PrimitiveValue execProgram(
         Path directory,
-        TypeName type,
+        ScalarType type,
         String methodName,
         List<PrimitiveValue> arguments,
-        TypeName returnType) throws IOException, InterruptedException;
+        ScalarType returnType) throws IOException, InterruptedException;
 
     private Path directoryName(Path path, int length) {
         for (int i = 0; i < length; i++) {
@@ -267,7 +267,7 @@ public abstract class CompilerTests {
         return path;
     }
 
-    private PrimitiveValue exec(TypeName returnType, String source) {
+    private PrimitiveValue exec(ScalarType returnType, String source) {
         try {
             String javaClass =
                 "package com.example;" +
@@ -280,7 +280,7 @@ public abstract class CompilerTests {
                 Files.write(directoryPath.resolve("com/example/Example.java"), list(javaClass));
                 return execProgram(
                     directoryPath,
-                    TypeName.of("com.example.Example"),
+                    ScalarType.of("com.example.Example"),
                     "main",
                     list(),
                     returnType);
@@ -300,7 +300,7 @@ public abstract class CompilerTests {
         return evalExpression(IntegerValue.REF, expressionSource);
     }
 
-    private PrimitiveValue evalExpression(TypeName type, String expressionSource) {
+    private PrimitiveValue evalExpression(ScalarType type, String expressionSource) {
         return exec(type, "return " + expressionSource + ";");
     }
 
diff --git a/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java b/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
index 67ce611..e0cd72e 100644
--- a/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/JavaToInterpreterTests.java
@@ -1,7 +1,7 @@
 package org.zwobble.couscous.tests;
 
 import com.google.common.collect.ImmutableList;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.ast.TypeNode;
 import org.zwobble.couscous.frontends.java.JavaFrontend;
 import org.zwobble.couscous.interpreter.Interpreter;
@@ -22,10 +22,10 @@ public class JavaToInterpreterTests extends CompilerTests {
     @Override
     protected PrimitiveValue execProgram(
         Path directory,
-        TypeName type,
+        ScalarType type,
         String methodName,
         List<PrimitiveValue> arguments,
-        TypeName returnType
+        ScalarType returnType
     ) throws IOException, InterruptedException {
         JavaFrontend frontend = new JavaFrontend();
         List<TypeNode> classNodes = frontend.readSourceDirectory(list(directory), directory);
diff --git a/src/test/java/org/zwobble/couscous/tests/JavaToPythonTests.java b/src/test/java/org/zwobble/couscous/tests/JavaToPythonTests.java
index 6b9f6ed..ecc1fc9 100644
--- a/src/test/java/org/zwobble/couscous/tests/JavaToPythonTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/JavaToPythonTests.java
@@ -1,7 +1,7 @@
 package org.zwobble.couscous.tests;
 
 import org.zwobble.couscous.CouscousCompiler;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.backends.python.PythonBackend;
 import org.zwobble.couscous.frontends.java.JavaFrontend;
 import org.zwobble.couscous.tests.backends.python.PythonMethodRunner;
@@ -18,10 +18,10 @@ import static org.zwobble.couscous.util.ExtraLists.list;
 public class JavaToPythonTests extends CompilerTests {
     protected PrimitiveValue execProgram(
             Path directory,
-            TypeName type,
+            ScalarType type,
             String methodName,
             List<PrimitiveValue> arguments,
-            TypeName returnType) throws IOException, InterruptedException {
+            ScalarType returnType) throws IOException, InterruptedException {
 
         Path directoryPath = Files.createTempDirectory(null);
         try {
diff --git a/src/test/java/org/zwobble/couscous/tests/MethodRunner.java b/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
index 8fde77f..cf7b884 100644
--- a/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/MethodRunner.java
@@ -3,6 +3,8 @@ package org.zwobble.couscous.tests;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
+import org.zwobble.couscous.ast.types.Type;
 import org.zwobble.couscous.values.PrimitiveValue;
 
 import java.util.List;
@@ -12,9 +14,10 @@ import static org.zwobble.couscous.util.ExtraLists.list;
 public interface MethodRunner {
     PrimitiveValue runMethod(
         List<TypeNode> classNodes,
-        TypeName className,
+        ScalarType className,
         String methodName,
-        List<PrimitiveValue> arguments, TypeName returnType);
+        List<PrimitiveValue> arguments,
+        Type returnType);
 
     default PrimitiveValue evalExpression(List<TypeNode> classes, ExpressionNode expression) {
         ClassNode programNode = ClassNode.builder("Program")
diff --git a/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java b/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
index 8e5d7c8..f0780d5 100644
--- a/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/ValueObjectTests.java
@@ -7,6 +7,8 @@ import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameters;
 import org.zwobble.couscous.ast.*;
 import org.zwobble.couscous.ast.identifiers.Identifier;
+import org.zwobble.couscous.ast.types.ScalarType;
+import org.zwobble.couscous.ast.types.Type;
 import org.zwobble.couscous.util.ExtraArrays;
 import org.zwobble.couscous.values.PrimitiveValue;
 import org.zwobble.couscous.values.StringValue;
@@ -60,11 +62,12 @@ public class ValueObjectTests {
             {MethodNode.class},
             {OperationNode.class},
             {ReturnNode.class},
+            {ScalarType.class},
             {StaticReceiver.class},
             {TernaryConditionalNode.class},
             {ThisReferenceNode.class},
             {TypeCoercionNode.class},
-            {TypeName.class},
+            {ScalarType.class},
             {VariableDeclaration.class},
             {VariableReferenceNode.class},
             {WhileNode.class}
@@ -153,6 +156,8 @@ public class ValueObjectTests {
             return generateFirstInstance(InstanceReceiver.class);
         } else if (type.equals(AssignableExpressionNode.class)) {
             return generateFirstInstance(VariableReferenceNode.class);
+        } else if (type.equals(Type.class)) {
+            return generateFirstInstance(ScalarType.class);
         } else {
             return generateValue(type, ValueObjectTests::generateFirstInstance).instance;         
         }
@@ -181,6 +186,8 @@ public class ValueObjectTests {
             return generateSecondInstance(InstanceReceiver.class);
         } else if (type.equals(AssignableExpressionNode.class)) {
             return generateSecondInstance(VariableReferenceNode.class);
+        } else if (type.equals(Type.class)) {
+            return generateSecondInstance(ScalarType.class);
         } else {
             return generateValue(type, ValueObjectTests::generateSecondInstance).instance;           
         }
@@ -209,6 +216,8 @@ public class ValueObjectTests {
             return generateInstance(InstanceReceiver.class);
         } else if (type.equals(AssignableExpressionNode.class)) {
             return generateInstance(VariableReferenceNode.class);
+        } else if (type.equals(Type.class)) {
+            return generateInstance(ScalarType.class);
         } else {
             return generateValue(type, ValueObjectTests::generateInstance).instance;
         }
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
index 4e05266..a73a5ee 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpMethodRunner.java
@@ -4,7 +4,11 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterators;
 import org.hamcrest.Matchers;
 import org.zwobble.couscous.Backend;
-import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.LiteralNode;
+import org.zwobble.couscous.ast.MethodSignature;
+import org.zwobble.couscous.ast.TypeNode;
+import org.zwobble.couscous.ast.types.ScalarType;
+import org.zwobble.couscous.ast.types.Type;
 import org.zwobble.couscous.backends.Names;
 import org.zwobble.couscous.backends.csharp.CsharpBackend;
 import org.zwobble.couscous.backends.csharp.CsharpSerializer;
@@ -33,7 +37,7 @@ public class CsharpMethodRunner implements MethodRunner {
     private static final String NAMESPACE = "Couscous";
 
     @Override
-    public PrimitiveValue runMethod(List<TypeNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
+    public PrimitiveValue runMethod(List<TypeNode> classNodes, ScalarType className, String methodName, List<PrimitiveValue> arguments, Type returnType) {
         try {
             Path directoryPath = Files.createTempDirectory(null);
             Backend compiler = new CsharpBackend(directoryPath, NAMESPACE);
@@ -50,10 +54,10 @@ public class CsharpMethodRunner implements MethodRunner {
 
     public static PrimitiveValue runFunction(
         Path directoryPath,
-        TypeName className,
+        ScalarType className,
         String methodName,
         List<PrimitiveValue> arguments,
-        TypeName returnType)
+        Type returnType)
         throws IOException, InterruptedException
     {
         MethodSignature signature = new MethodSignature(
@@ -63,7 +67,7 @@ public class CsharpMethodRunner implements MethodRunner {
         String csharpMethodName = Names.toUniqueName(signature);
         String value = CsharpSerializer.serialize(
             staticMethodCall(
-                TypeName.of(NAMESPACE + "." + className.getQualifiedName()),
+                ScalarType.of(NAMESPACE + "." + className.getQualifiedName()),
                 csharpMethodName,
                 eagerMap(arguments, LiteralNode::literal),
                 returnType));
@@ -122,7 +126,7 @@ public class CsharpMethodRunner implements MethodRunner {
                     return value(StringValue.REF);
                 } else {
                     assertThat(value, Matchers.startsWith(NAMESPACE_PREFIX));
-                    return value(TypeName.of(value.substring(NAMESPACE_PREFIX.length())));
+                    return value(ScalarType.of(value.substring(NAMESPACE_PREFIX.length())));
                 }
             default:
                 throw new RuntimeException("Unhandled type: " + type);
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpSerializerTests.java b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpSerializerTests.java
index 493ba2b..d0a8c77 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpSerializerTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/csharp/CsharpSerializerTests.java
@@ -2,6 +2,7 @@ package org.zwobble.couscous.tests.backends.csharp;
 
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.backends.csharp.CsharpSerializer;
 import org.zwobble.couscous.tests.TestIds;
 import org.zwobble.couscous.values.BooleanValue;
@@ -51,19 +52,19 @@ public class CsharpSerializerTests {
 
     @Test
     public void typeLiteralUsesTypeOfOperator() {
-        String output = serialize(literal(TypeName.of("com.example.Example")));
+        String output = serialize(literal(ScalarType.of("com.example.Example")));
         assertEquals("typeof(com.example.Example)", output);
     }
 
     @Test
     public void variableReferenceWritesIdentifier() {
-        String output = serialize(reference(var(TestIds.ANY_ID, "x", TypeName.of("X"))));
+        String output = serialize(reference(var(TestIds.ANY_ID, "x", ScalarType.of("X"))));
         assertEquals("x", output);
     }
 
     @Test
     public void thisReferenceUsesThisKeyword() {
-        String output = serialize(thisReference(TypeName.of("X")));
+        String output = serialize(thisReference(ScalarType.of("X")));
         assertEquals("this", output);
     }
 
@@ -84,37 +85,37 @@ public class CsharpSerializerTests {
     @Test
     public void staticMethodCallWithNoArgumentsWritesStaticReceiver() {
         String output = serialize(staticMethodCall(
-            TypeName.of("X"),
+            ScalarType.of("X"),
             "y",
             list(),
-            TypeName.of("Y")));
+            ScalarType.of("Y")));
         assertEquals("X.y()", output);
     }
 
     @Test
     public void methodCallWithNoArgumentsWritesReceiver() {
         String output = serialize(methodCall(
-            reference(var(TestIds.ANY_ID, "x", TypeName.of("X"))),
+            reference(var(TestIds.ANY_ID, "x", ScalarType.of("X"))),
             "y",
             list(),
-            TypeName.of("Y")));
+            ScalarType.of("Y")));
         assertEquals("x.y()", output);
     }
 
     @Test
     public void methodCallWithArguments() {
         String output = serialize(methodCall(
-            reference(var(TestIds.ANY_ID, "x", TypeName.of("X"))),
+            reference(var(TestIds.ANY_ID, "x", ScalarType.of("X"))),
             "y",
             list(literal(1), literal(2)),
-            TypeName.of("Y")));
+            ScalarType.of("Y")));
         assertEquals("x.y(1, 2)", output);
     }
 
     @Test
     public void constructorCallWithNoArguments() {
         String output = serialize(constructorCall(
-            TypeName.of("X"),
+            ScalarType.of("X"),
             list()));
         assertEquals("new X()", output);
     }
@@ -122,7 +123,7 @@ public class CsharpSerializerTests {
     @Test
     public void constructorCallWithArguments() {
         String output = serialize(constructorCall(
-            TypeName.of("X"),
+            ScalarType.of("X"),
             list(literal(1), literal(2))));
         assertEquals("new X(1, 2)", output);
     }
@@ -143,18 +144,18 @@ public class CsharpSerializerTests {
     @Test
     public void fieldAccessSeparatesReceiverAndNameWithDot() {
         String output = serialize(fieldAccess(
-            reference(var(TestIds.ANY_ID, "x", TypeName.of("X"))),
+            reference(var(TestIds.ANY_ID, "x", ScalarType.of("X"))),
             "y",
-            TypeName.of("Y")));
+            ScalarType.of("Y")));
         assertEquals("x.y", output);
     }
 
     @Test
     public void staticFieldAccessSeparatesReceiverAndNameWithDot() {
         String output = serialize(fieldAccess(
-            TypeName.of("X"),
+            ScalarType.of("X"),
             "y",
-            TypeName.of("Y")));
+            ScalarType.of("Y")));
         assertEquals("X.y", output);
     }
 
@@ -181,7 +182,7 @@ public class CsharpSerializerTests {
         String output = serialize(localVariableDeclaration(
             TestIds.ANY_ID,
             "x",
-            TypeName.of("string"),
+            ScalarType.of("string"),
             literal("[value]")));
         assertEquals("string x = \"[value]\";\n", output);
     }
@@ -206,7 +207,7 @@ public class CsharpSerializerTests {
     @Test
     public void methodCanHaveVoidReturnType() {
         String output = serialize(MethodNode.staticMethod("nothing")
-            .returns(TypeName.of("void"))
+            .returns(ScalarType.of("void"))
             .build());
         assertEquals("public static void nothing() {\n}\n", output);
     }
@@ -214,7 +215,7 @@ public class CsharpSerializerTests {
     @Test
     public void instanceMethodHasNoStaticKeword() {
         String output = serialize(MethodNode.builder("nothing")
-            .returns(TypeName.of("void"))
+            .returns(ScalarType.of("void"))
             .build());
         assertEquals("public void nothing() {\n}\n", output);
     }
@@ -222,7 +223,7 @@ public class CsharpSerializerTests {
     @Test
     public void methodWithReturnType() {
         MethodNode methodNode = MethodNode.staticMethod("nothing")
-            .returns(TypeName.of("X"))
+            .returns(ScalarType.of("X"))
             .build();
 
         String output = serialize(methodNode);
@@ -233,9 +234,9 @@ public class CsharpSerializerTests {
     @Test
     public void methodWithArguments() {
         MethodNode methodNode = MethodNode.staticMethod("nothing")
-            .argument(formalArg(var(TestIds.id("x"), "x", TypeName.of("X"))))
-            .argument(formalArg(var(TestIds.id("y"), "y", TypeName.of("Y"))))
-            .returns(TypeName.of("void"))
+            .argument(formalArg(var(TestIds.id("x"), "x", ScalarType.of("X"))))
+            .argument(formalArg(var(TestIds.id("y"), "y", ScalarType.of("Y"))))
+            .returns(ScalarType.of("void"))
             .build();
 
         String output = serialize(methodNode);
@@ -246,7 +247,7 @@ public class CsharpSerializerTests {
     @Test
     public void methodHasSerializedBody() {
         MethodNode method = MethodNode.staticMethod("nothing")
-            .returns(TypeName.of("void"))
+            .returns(ScalarType.of("void"))
             .statement(returns(literal(true)))
             .build();
         String output = serialize(method);
@@ -301,7 +302,7 @@ public class CsharpSerializerTests {
     @Test
     public void constructorHasSerializedBody() {
         ConstructorNode constructor = ConstructorNode.constructor(
-            list(formalArg(var(TestIds.ANY_ID, "x", TypeName.of("X")))),
+            list(formalArg(var(TestIds.ANY_ID, "x", ScalarType.of("X")))),
             list(expressionStatement(literal(true))));
         ClassNode classNode = ClassNode.builder("com.example.Example")
             .constructor(constructor)
@@ -316,8 +317,8 @@ public class CsharpSerializerTests {
     @Test
     public void classWithFields() {
         ClassNode classNode = ClassNode.builder("com.example.Example")
-            .staticField("x", TypeName.of("X"))
-            .field("y", TypeName.of("Y"))
+            .staticField("x", ScalarType.of("X"))
+            .field("y", ScalarType.of("Y"))
             .build();
 
         String output = serialize(classNode);
@@ -327,7 +328,7 @@ public class CsharpSerializerTests {
 
     @Test
     public void interfaceIsInNamespace() {
-        Node node = new ClassNodeBuilder(TypeName.of("com.example.Example")).buildInterface();
+        Node node = new ClassNodeBuilder(ScalarType.of("com.example.Example")).buildInterface();
 
         String output = serialize(node);
 
@@ -336,7 +337,7 @@ public class CsharpSerializerTests {
 
     @Test
     public void interfaceWithTypeParameters() {
-        Node node = new ClassNodeBuilder(TypeName.of("com.example.Example"))
+        Node node = new ClassNodeBuilder(ScalarType.of("com.example.Example"))
             .addTypeParameter("T")
             .addTypeParameter("U")
             .buildInterface();
@@ -348,7 +349,7 @@ public class CsharpSerializerTests {
 
     @Test
     public void interfaceWithSuperTypes() {
-        Node node = new ClassNodeBuilder(TypeName.of("com.example.Example"))
+        Node node = new ClassNodeBuilder(ScalarType.of("com.example.Example"))
             .addSuperType("com.example.Base")
             .buildInterface();
 
@@ -360,7 +361,7 @@ public class CsharpSerializerTests {
     @Test
     public void interfaceWithMethod() {
         MethodNode method = MethodNode.builder("get").isAbstract().returns(IntegerValue.REF).build();
-        Node node = new ClassNodeBuilder(TypeName.of("com.example.Example"))
+        Node node = new ClassNodeBuilder(ScalarType.of("com.example.Example"))
             .method(method)
             .buildInterface();
 
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/csharp/JavaToCsharpTests.java b/src/test/java/org/zwobble/couscous/tests/backends/csharp/JavaToCsharpTests.java
index 4c7e56b..68d270d 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/csharp/JavaToCsharpTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/csharp/JavaToCsharpTests.java
@@ -3,7 +3,7 @@ package org.zwobble.couscous.tests.backends.csharp;
 import org.junit.Ignore;
 import org.junit.Test;
 import org.zwobble.couscous.CouscousCompiler;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.backends.csharp.CsharpBackend;
 import org.zwobble.couscous.frontends.java.JavaFrontend;
 import org.zwobble.couscous.tests.CompilerTests;
@@ -25,10 +25,10 @@ public class JavaToCsharpTests extends CompilerTests {
 
     protected PrimitiveValue execProgram(
         Path directory,
-        TypeName type,
+        ScalarType type,
         String methodName,
         List<PrimitiveValue> arguments,
-        TypeName returnType) throws IOException, InterruptedException
+        ScalarType returnType) throws IOException, InterruptedException
     {
         Path directoryPath = Files.createTempDirectory(null);
         try {
diff --git a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
index 2b0d2ce..ce91549 100644
--- a/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
+++ b/src/test/java/org/zwobble/couscous/tests/backends/python/PythonMethodRunner.java
@@ -3,8 +3,9 @@ package org.zwobble.couscous.tests.backends.python;
 import com.google.common.base.Joiner;
 import org.hamcrest.Matchers;
 import org.zwobble.couscous.ast.MethodSignature;
-import org.zwobble.couscous.ast.TypeName;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.ast.TypeNode;
+import org.zwobble.couscous.ast.types.Type;
 import org.zwobble.couscous.backends.Names;
 import org.zwobble.couscous.backends.python.PythonBackend;
 import org.zwobble.couscous.backends.python.PythonCodeGenerator;
@@ -28,7 +29,7 @@ import static org.zwobble.couscous.values.PrimitiveValues.value;
 
 public class PythonMethodRunner implements MethodRunner {
     @Override
-    public PrimitiveValue runMethod(List<TypeNode> classNodes, TypeName className, String methodName, List<PrimitiveValue> arguments, TypeName returnType) {
+    public PrimitiveValue runMethod(List<TypeNode> classNodes, ScalarType className, String methodName, List<PrimitiveValue> arguments, Type returnType) {
         try {
             Path directoryPath = Files.createTempDirectory(null);
             PythonBackend compiler = new PythonBackend(directoryPath, "couscous");
@@ -45,10 +46,10 @@ public class PythonMethodRunner implements MethodRunner {
 
     public static PrimitiveValue runFunction(
             Path directoryPath,
-            TypeName className,
+            ScalarType className,
             String methodName,
             List<PrimitiveValue> arguments,
-            TypeName returnType)
+            Type returnType)
             throws IOException, InterruptedException {
         
         String argumentsString = Joiner.on(", ").join(arguments.stream().map(PythonCodeGenerator::generateCode).map(PythonSerializer::serialize).iterator());
@@ -82,7 +83,7 @@ public class PythonMethodRunner implements MethodRunner {
             case "<class 'type'>":
                 String typeName = value.substring(value.indexOf("'") + 1, value.lastIndexOf("'"));
                 assertThat(typeName, Matchers.startsWith(PACKAGE_PREFIX));
-                return value(TypeName.of(typeName.substring(PACKAGE_PREFIX.length(), typeName.lastIndexOf("."))));
+                return value(ScalarType.of(typeName.substring(PACKAGE_PREFIX.length(), typeName.lastIndexOf("."))));
             default:
                 throw new RuntimeException("Unhandled type: " + type);
         }
diff --git a/src/test/java/org/zwobble/couscous/tests/frontends/java/ExpressionReadingTests.java b/src/test/java/org/zwobble/couscous/tests/frontends/java/ExpressionReadingTests.java
index 2f59e57..e73b63b 100644
--- a/src/test/java/org/zwobble/couscous/tests/frontends/java/ExpressionReadingTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/frontends/java/ExpressionReadingTests.java
@@ -2,6 +2,7 @@ package org.zwobble.couscous.tests.frontends.java;
 
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.values.BooleanValue;
 import org.zwobble.couscous.values.IntegerValue;
 import org.zwobble.couscous.values.ObjectValues;
@@ -43,7 +44,7 @@ public class ExpressionReadingTests {
     @Test
     public void canReadThisReference() {
         assertEquals(
-            thisReference(TypeName.of("com.example.Example")),
+            thisReference(ScalarType.of("com.example.Example")),
             readExpressionInInstanceMethod("com.example.Example", "this"));
     }
 
@@ -59,7 +60,7 @@ public class ExpressionReadingTests {
             "private String name;");
 
         assertEquals(
-            list(field("name", TypeName.of("java.lang.String"))),
+            list(field("name", ScalarType.of("java.lang.String"))),
             classNode.getFields());
     }
 
@@ -69,7 +70,7 @@ public class ExpressionReadingTests {
             "private static String name;");
 
         assertEquals(
-            list(staticField("name", TypeName.of("java.lang.String"))),
+            list(staticField("name", ScalarType.of("java.lang.String"))),
             classNode.getFields());
     }
 
@@ -93,7 +94,7 @@ public class ExpressionReadingTests {
         ReturnNode returnNode = (ReturnNode) classNode.getMethods().get(0).getBody().get().get(0);
         assertEquals(
             fieldAccess(
-                thisReference(TypeName.of("com.example.Example")),
+                thisReference(ScalarType.of("com.example.Example")),
                 "name",
                 StringValue.REF),
             returnNode.getValue());
@@ -119,7 +120,7 @@ public class ExpressionReadingTests {
         ReturnNode returnNode = (ReturnNode) classNode.getMethods().get(0).getBody().get().get(0);
         assertEquals(
             fieldAccess(
-                TypeName.of("com.example.Example"),
+                ScalarType.of("com.example.Example"),
                 "name",
                 StringValue.REF),
             returnNode.getValue());
@@ -149,7 +150,7 @@ public class ExpressionReadingTests {
 
         assertEquals(
             methodCall(
-                ThisReferenceNode.thisReference(TypeName.of("com.example.Example")),
+                ThisReferenceNode.thisReference(ScalarType.of("com.example.Example")),
                 "loop",
                 list(),
                 StringValue.REF),
@@ -160,7 +161,7 @@ public class ExpressionReadingTests {
     public void canReadStaticMethodCalls() {
         assertEquals(
             staticMethodCall(
-                TypeName.of("java.lang.Integer"),
+                ScalarType.of("java.lang.Integer"),
                 "parseInt",
                 list(literal("42")),
                 IntegerValue.REF),
@@ -177,7 +178,7 @@ public class ExpressionReadingTests {
 
         assertEquals(
             staticMethodCall(
-                TypeName.of("com.example.Example"),
+                ScalarType.of("com.example.Example"),
                 "loop",
                 list(),
                 StringValue.REF),
@@ -187,7 +188,7 @@ public class ExpressionReadingTests {
     @Test
     public void canReadConstructorCalls() {
         assertEquals(
-            constructorCall(TypeName.of("java.lang.String"), list(literal("_"))),
+            constructorCall(ScalarType.of("java.lang.String"), list(literal("_"))),
             readExpression("String", "new String(\"_\")"));
     }
 
@@ -205,14 +206,14 @@ public class ExpressionReadingTests {
     public void canUseOperatorsOnReferences() {
         assertEquals(
             same(
-                constructorCall(TypeName.of("java.lang.Object"), emptyList()),
-                constructorCall(TypeName.of("java.lang.Object"), emptyList())),
+                constructorCall(ScalarType.of("java.lang.Object"), emptyList()),
+                constructorCall(ScalarType.of("java.lang.Object"), emptyList())),
             readBooleanExpression("new Object() == new Object()"));
 
         assertEquals(
             not(same(
-                constructorCall(TypeName.of("java.lang.Object"), emptyList()),
-                constructorCall(TypeName.of("java.lang.Object"), emptyList()))),
+                constructorCall(ScalarType.of("java.lang.Object"), emptyList()),
+                constructorCall(ScalarType.of("java.lang.Object"), emptyList()))),
             readBooleanExpression("new Object() != new Object()"));
     }
 
@@ -270,13 +271,13 @@ public class ExpressionReadingTests {
         assertEquals(
             equal(
                 literal(1),
-                unboxInt(constructorCall(TypeName.of("java.lang.Integer"), list(literal(1))))),
+                unboxInt(constructorCall(ScalarType.of("java.lang.Integer"), list(literal(1))))),
             readBooleanExpression("1 == new Integer(1)"));
 
         assertEquals(
             notEqual(
                 literal(1),
-                unboxInt(constructorCall(TypeName.of("java.lang.Integer"), list(literal(1))))),
+                unboxInt(constructorCall(ScalarType.of("java.lang.Integer"), list(literal(1))))),
             readBooleanExpression("1 != new Integer(1)"));
     }
 
@@ -299,8 +300,8 @@ public class ExpressionReadingTests {
     public void integerOperatorUnboxesWhenBothOperandsAreBoxed() {
         assertEquals(
             integerAdd(
-                unboxInt(constructorCall(TypeName.of("java.lang.Integer"), list(literal(1)))),
-                unboxInt(constructorCall(TypeName.of("java.lang.Integer"), list(literal(2))))),
+                unboxInt(constructorCall(ScalarType.of("java.lang.Integer"), list(literal(1)))),
+                unboxInt(constructorCall(ScalarType.of("java.lang.Integer"), list(literal(2))))),
             readIntExpression("new Integer(1) + new Integer(2)"));
     }
 
@@ -323,7 +324,7 @@ public class ExpressionReadingTests {
         assertEquals(
             assign(
                 fieldAccess(
-                    thisReference(TypeName.of("com.example.Example")),
+                    thisReference(ScalarType.of("com.example.Example")),
                     "name",
                     StringValue.REF),
                 literal("blah")),
@@ -342,7 +343,7 @@ public class ExpressionReadingTests {
         assertEquals(
             assign(
                 fieldAccess(
-                    thisReference(TypeName.of("com.example.Example")),
+                    thisReference(ScalarType.of("com.example.Example")),
                     "value",
                     ObjectValues.OBJECT),
                 typeCoercion(literal(4), ObjectValues.OBJECT)),
diff --git a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
index 4694f85..5745adb 100644
--- a/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/frontends/java/JavaReaderTests.java
@@ -2,6 +2,7 @@ package org.zwobble.couscous.tests.frontends.java;
 
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.values.IntegerValue;
 import org.zwobble.couscous.values.ObjectValues;
 import org.zwobble.couscous.values.StringValue;
@@ -77,7 +78,7 @@ public class JavaReaderTests {
         MethodNode method = classNode.getMethods().get(0);
         FormalArgumentNode argument = method.getArguments().get(0);
         assertEquals("value", argument.getName());
-        assertEquals(TypeName.of("int"), argument.getType());
+        assertEquals(ScalarType.of("int"), argument.getType());
         assertEquals(1, method.getArguments().size());
         
         ReturnNode returnNode = (ReturnNode)method.getBody().get().get(0);
@@ -89,7 +90,7 @@ public class JavaReaderTests {
         assertEquals(
             expressionStatement(
                 staticMethodCall(
-                    TypeName.of("java.lang.Integer"),
+                    ScalarType.of("java.lang.Integer"),
                     "parseInt",
                     list(literal("42")),
                     IntegerValue.REF)),
@@ -179,7 +180,7 @@ public class JavaReaderTests {
         assertEquals(
             list(assignStatement(
                 fieldAccess(
-                    thisReference(TypeName.of("com.example.Example")),
+                    thisReference(ScalarType.of("com.example.Example")),
                     "name",
                     StringValue.REF),
                 literal("Flaws"))),
@@ -202,13 +203,13 @@ public class JavaReaderTests {
             list(
                 assignStatement(
                     fieldAccess(
-                        thisReference(TypeName.of("com.example.Example")),
+                        thisReference(ScalarType.of("com.example.Example")),
                         "year",
                         IntegerValue.REF),
                     literal(2013)),
                 assignStatement(
                     fieldAccess(
-                        thisReference(TypeName.of("com.example.Example")),
+                        thisReference(ScalarType.of("com.example.Example")),
                         "name",
                         StringValue.REF),
                     literal("Flaws"))),
@@ -230,13 +231,13 @@ public class JavaReaderTests {
             list(
                 assignStatement(
                     fieldAccess(
-                        thisReference(TypeName.of("com.example.Example")),
+                        thisReference(ScalarType.of("com.example.Example")),
                         "year",
                         IntegerValue.REF),
                     literal(2013)),
                 assignStatement(
                     fieldAccess(
-                        thisReference(TypeName.of("com.example.Example")),
+                        thisReference(ScalarType.of("com.example.Example")),
                         "name",
                         StringValue.REF),
                     literal("Flaws"))),
@@ -256,7 +257,7 @@ public class JavaReaderTests {
         assertEquals(
             list(assignStatement(
                 fieldAccess(
-                    TypeName.of("com.example.Example"),
+                    ScalarType.of("com.example.Example"),
                     "name",
                     StringValue.REF),
                 literal("Flaws"))),
@@ -273,7 +274,7 @@ public class JavaReaderTests {
         assertEquals(
             list(assignStatement(
                 fieldAccess(
-                    TypeName.of("com.example.Example"),
+                    ScalarType.of("com.example.Example"),
                     "name",
                     StringValue.REF),
                 literal("Flaws"))),
@@ -287,7 +288,7 @@ public class JavaReaderTests {
         
         MethodNode method = classNode.getMethods().get(0);
         assertEquals(
-            list(annotation(TypeName.of("java.lang.Deprecated"))),
+            list(annotation(ScalarType.of("java.lang.Deprecated"))),
             method.getAnnotations());
     }
 
@@ -309,7 +310,7 @@ public class JavaReaderTests {
         List<TypeNode> classes = readSource("com/example/Example.java", source);
         assertThat(classes, hasSize(1));
         InterfaceNode classNode = (InterfaceNode) classes.get(0);
-        assertEquals(TypeName.of("com.example.Example"), classNode.getName());
+        assertEquals(ScalarType.of("com.example.Example"), classNode.getName());
         assertEquals(list(), classNode.getMethods());
         assertEquals(set(), classNode.getSuperTypes());
         assertEquals(list(), classNode.getTypeParameters());
@@ -322,7 +323,7 @@ public class JavaReaderTests {
         List<TypeNode> classes = readSource("com/example/Example.java", source);
         assertThat(classes, hasSize(1));
         ClassNode classNode = (ClassNode) classes.get(0);
-        assertEquals(TypeName.of("com.example.Example"), classNode.getName());
+        assertEquals(ScalarType.of("com.example.Example"), classNode.getName());
         assertEquals(list(formalTypeParameter("T")), classNode.getTypeParameters());
     }
 
@@ -333,7 +334,7 @@ public class JavaReaderTests {
         List<TypeNode> classes = readSource("com/example/Example.java", source);
         assertThat(classes, hasSize(1));
         InterfaceNode classNode = (InterfaceNode) classes.get(0);
-        assertEquals(TypeName.of("com.example.Example"), classNode.getName());
+        assertEquals(ScalarType.of("com.example.Example"), classNode.getName());
         assertEquals(list(formalTypeParameter("T")), classNode.getTypeParameters());
     }
 
@@ -344,9 +345,9 @@ public class JavaReaderTests {
         List<TypeNode> classes = readSource("com/example/Example.java", source);
         assertThat(classes, hasSize(1));
         InterfaceNode classNode = (InterfaceNode) classes.get(0);
-        assertEquals(TypeName.of("com.example.Example"), classNode.getName());
+        assertEquals(ScalarType.of("com.example.Example"), classNode.getName());
         assertEquals(list(), classNode.getMethods());
-        assertThat(classNode.getSuperTypes(), contains(TypeName.of("java.util.function.IntSupplier")));
+        assertThat(classNode.getSuperTypes(), contains(ScalarType.of("java.util.function.IntSupplier")));
     }
 
     @Test
diff --git a/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java b/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
index 902febd..73576dd 100644
--- a/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/interpreter/EvaluatorTests.java
@@ -3,6 +3,7 @@ package org.zwobble.couscous.tests.interpreter;
 import com.google.common.collect.ImmutableMap;
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
 import org.zwobble.couscous.interpreter.Environment;
 import org.zwobble.couscous.interpreter.JavaProject;
 import org.zwobble.couscous.interpreter.MapBackedProject;
@@ -171,7 +172,7 @@ public class EvaluatorTests extends BackendEvalTests {
 
     @Test
     public void cannotSetValueOfInstanceFieldAsThoughItIsAStaticField() {
-        TypeName type = TypeName.of("com.example.Example");
+        ScalarType type = ScalarType.of("com.example.Example");
         ClassNode classNode = ClassNode.builder(type)
             .field("value", IntegerValue.REF)
             .constructor(constructor -> constructor
diff --git a/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java b/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
index c8dd2fb..d9cef51 100644
--- a/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
+++ b/src/test/java/org/zwobble/couscous/tests/interpreter/InterpreterMethodTests.java
@@ -2,6 +2,8 @@ package org.zwobble.couscous.tests.interpreter;
 
 import org.junit.Test;
 import org.zwobble.couscous.ast.*;
+import org.zwobble.couscous.ast.types.ScalarType;
+import org.zwobble.couscous.ast.types.Type;
 import org.zwobble.couscous.interpreter.Interpreter;
 import org.zwobble.couscous.interpreter.JavaProject;
 import org.zwobble.couscous.interpreter.Project;
@@ -106,10 +108,10 @@ public class InterpreterMethodTests extends BackendMethodTests {
             @Override
             public PrimitiveValue runMethod(
                 List<TypeNode> classNodes,
-                TypeName className,
+                ScalarType className,
                 String methodName,
                 List<PrimitiveValue> arguments,
-                TypeName returnType) {
+                Type returnType) {
                 
                 Project project = JavaProject.of(classNodes);
                 Interpreter interpreter = new Interpreter(project);