[Voi-99] Very basic generic function support (#35)

* BnrCall gc support

* Fix parsing bug: commas are not operators.

* Potential basic generic type resolution

* Semi working

* Fix typechecking bug

* Detect duplicate var defs

* Use type args to find a good fn match

* Forgot to add these changes to last commit

* IT WORKS!

* Add unit test for generics

* Cleanup

src/__tests__/compiler.test.ts

@@ -1,6 +1,7 @@
 import {
   e2eVoidText,
   gcVoidText,
+  genericsText,
   goodTypeInferenceText,
   tcoText,
 } from "./fixtures/e2e-file.js";
@@ -36,23 +37,34 @@ describe("E2E Compiler Pipeline", () => {
     const test4 = getWasmFn("test4", instance);
     const test5 = getWasmFn("test5", instance);
     const test6 = getWasmFn("test6", instance);
+    const test7 = getWasmFn("test7", instance);
     assert(test1, "Test1 exists");
     assert(test2, "Test2 exists");
     assert(test3, "Test3 exists");
     assert(test4, "Test4 exists");
-    assert(test5, "Test3 exists");
-    assert(test6, "Test4 exists");
+    assert(test5, "Test5 exists");
+    assert(test6, "Test6 exists");
+    assert(test7, "Test7 exists");
     t.expect(test1(), "test 1 returns correct value").toEqual(13);
     t.expect(test2(), "test 2 returns correct value").toEqual(1);
     t.expect(test3(), "test 3 returns correct value").toEqual(2);
     t.expect(test4(), "test 4 returns correct value").toEqual(52);
-    t.expect(test5(), "test 5 returns correct value").toEqual(21);
-    t.expect(test6(), "test 6 returns correct value").toEqual(-1);
+    t.expect(test5(), "test 5 returns correct value").toEqual(52);
+    t.expect(test6(), "test 6 returns correct value").toEqual(21);
+    t.expect(test7(), "test 7 returns correct value").toEqual(-1);
   });
 
   test("Compiler can do tco", async (t) => {
     const spy = vi.spyOn(rCallUtil, "returnCall");
     await compile(tcoText);
     t.expect(spy).toHaveBeenCalledTimes(1);
   });
+
+  test("Generic fn compilation", async (t) => {
+    const mod = await compile(genericsText);
+    const instance = getWasmInstance(mod);
+    const main = getWasmFn("main", instance);
+    assert(main, "Main exists");
+    t.expect(main(), "main 1 returns correct value").toEqual(143);
+  });
 });

src/__tests__/fixtures/e2e-file.ts

@@ -76,13 +76,18 @@ pub fn test4()
   let vec = Point { x: 52, y: 2, z: 21 }
   vec.get_x()
 
-// Test match type guard (Point case), should return 21
+// Test match type guard (Pointy case), should return 52
 pub fn test5()
+  let vec = Pointy { x: 52, y: 2, z: 21 }
+  get_num_from_vec_sub_obj(vec)
+
+// Test match type guard (Point case), should return 21
+pub fn test6()
   let vec = Point { x: 52, y: 2, z: 21 }
   get_num_from_vec_sub_obj(vec)
 
 // Test match type guard (else case), should return -1
-pub fn test6()
+pub fn test7()
   let vec = Bitly { x: 52, y: 2, z: 21 }
   get_num_from_vec_sub_obj(vec)
 `;
@@ -114,3 +119,18 @@ fn fib_alias(n: i32, a: i64, b: i64) -> i64
 pub fn main() -> i64
   fib(10, 0i64, 1i64)
 `;
+
+export const genericsText = `
+use std::all
+
+type DSArrayI32 = DSArray<i32>
+
+pub fn main()
+  let arr2 = ds_array_init<f64>(10)
+  arr2.set<f64>(0, 1.5)
+  arr2.get<f64>(0)
+
+  let arr: DSArrayI32 = ds_array_init<i32>(10)
+  arr.set<i32>(9, 143)
+  arr.get<i32>(9)
+`;

src/assembler.ts

@@ -4,7 +4,12 @@ import { Expr } from "./syntax-objects/expr.js";
 import { Fn } from "./syntax-objects/fn.js";
 import { Identifier } from "./syntax-objects/identifier.js";
 import { Int } from "./syntax-objects/int.js";
-import { Type, Primitive, ObjectType } from "./syntax-objects/types.js";
+import {
+  Type,
+  Primitive,
+  ObjectType,
+  DSArrayType,
+} from "./syntax-objects/types.js";
 import { Variable } from "./syntax-objects/variable.js";
 import { Block } from "./syntax-objects/block.js";
 import { Declaration } from "./syntax-objects/declaration.js";
@@ -17,7 +22,8 @@ import {
   refCast,
   structGetFieldValue,
 } from "./lib/binaryen-gc/index.js";
-import { HeapTypeRef } from "./lib/binaryen-gc/types.js";
+import * as gc from "./lib/binaryen-gc/index.js";
+import { TypeRef } from "./lib/binaryen-gc/types.js";
 import { getExprType } from "./semantics/resolution/get-expr-type.js";
 import { Match, MatchCase } from "./syntax-objects/match.js";
 import { initExtensionHelpers } from "./assembler/extension-helpers.js";
@@ -264,14 +270,30 @@ const compileAssign = (opts: CompileExprOpts<Call>): number => {
 const compileBnrCall = (opts: CompileExprOpts<Call>): number => {
   const { expr } = opts;
   const funcId = expr.labeledArgAt(0) as Identifier;
-  const argTypes = expr.labeledArgAt(1) as Call;
-  const namespace = argTypes.identifierArgAt(0).value;
-  const args = expr.labeledArgAt(3) as Call;
-  const func = (opts.mod as any)[namespace][funcId.value];
+  const namespace = (expr.labeledArgAt(1) as Identifier).value;
+  const args = expr.labeledArgAt(2) as Call;
+
+  const func =
+    namespace === "gc"
+      ? (...args: unknown[]) => (gc as any)[funcId.value](opts.mod, ...args)
+      : (opts.mod as any)[namespace][funcId.value];
+
   return func(
-    ...(args.argArrayMap((expr: Expr) =>
-      compileExpression({ ...opts, expr })
-    ) ?? [])
+    ...(args.argArrayMap((expr: Expr) => {
+      if (expr?.isCall() && expr.calls("BnrType")) {
+        const type = getExprType(expr.typeArgs?.at(0));
+        if (!type) return opts.mod.nop();
+        return mapBinaryenType(opts, type);
+      }
+
+      if (expr?.isCall() && expr.calls("BnrConst")) {
+        const arg = expr.argAt(0);
+        if (!arg) return opts.mod.nop();
+        if ("value" in arg) return arg.value;
+      }
+
+      return compileExpression({ ...opts, expr });
+    }) ?? [])
   );
 };
 
@@ -287,6 +309,17 @@ const compileVariable = (opts: CompileExprOpts<Variable>): number => {
 
 const compileFunction = (opts: CompileExprOpts<Fn>): number => {
   const { expr: fn, mod } = opts;
+  if (fn.genericInstances) {
+    fn.genericInstances.forEach((instance) =>
+      compileFunction({ ...opts, expr: instance })
+    );
+    return mod.nop();
+  }
+
+  if (fn.typeParameters) {
+    return mod.nop();
+  }
+
   const parameterTypes = getFunctionParameterTypes(opts, fn);
   const returnType = mapBinaryenType(opts, fn.getReturnType());
 
@@ -378,20 +411,25 @@ const mapBinaryenType = (opts: CompileExprOpts, type: Type): binaryen.Type => {
   if (isPrimitiveId(type, "i64")) return binaryen.i64;
   if (isPrimitiveId(type, "f64")) return binaryen.f64;
   if (isPrimitiveId(type, "void")) return binaryen.none;
-  if (type.isObjectType()) {
-    return type.binaryenType ? type.binaryenType : buildObjectType(opts, type);
-  }
+  if (type.isObjectType()) return buildObjectType(opts, type);
+  if (type.isDSArrayType()) return buildDSArrayType(opts, type);
   throw new Error(`Unsupported type ${type}`);
 };
 
 const isPrimitiveId = (type: Type, id: Primitive) =>
   type.isPrimitiveType() && type.name.value === id;
 
+const buildDSArrayType = (opts: CompileExprOpts, type: DSArrayType) => {
+  if (type.binaryenType) return type.binaryenType;
+  const mod = opts.mod;
+  const elemType = mapBinaryenType(opts, type.elemType!);
+  type.binaryenType = gc.defineArrayType(mod, elemType, true, type.id);
+  return type.binaryenType;
+};
+
 /** TODO: Skip building types for object literals that are part of an initializer of an obj */
-const buildObjectType = (
-  opts: CompileExprOpts,
-  obj: ObjectType
-): HeapTypeRef => {
+const buildObjectType = (opts: CompileExprOpts, obj: ObjectType): TypeRef => {
+  if (obj.binaryenType) return obj.binaryenType;
   const mod = opts.mod;
 
   const binaryenType = defineStructType(mod, {

src/lib/binaryen-gc/index.ts

@@ -101,6 +101,14 @@ export const binaryenTypeToHeapType = (type: Type): HeapTypeRef => {
   return bin._BinaryenTypeGetHeapType(type);
 };
 
+// So we can use the from compileBnrCall
+export const modBinaryenTypeToHeapType = (
+  _mod: binaryen.Module,
+  type: Type
+): HeapTypeRef => {
+  return bin._BinaryenTypeGetHeapType(type);
+};
+
 export const refCast = (
   mod: binaryen.Module,
   ref: ExpressionRef,

src/lib/grammar.ts

@@ -2,7 +2,11 @@ import { Expr } from "../syntax-objects/expr.js";
 import { Identifier } from "../syntax-objects/identifier.js";
 
 export const isTerminator = (char: string) =>
-  isWhitespace(char) || isBracket(char) || isQuote(char) || isOpChar(char);
+  isWhitespace(char) ||
+  isBracket(char) ||
+  isQuote(char) ||
+  isOpChar(char) ||
+  char === ",";
 
 export const isQuote = newTest(["'", '"', "`"]);
 
@@ -19,7 +23,6 @@ export const isOpChar = newTest([
   ":",
   "?",
   ".",
-  ",",
   ";",
   "<",
   ">",

src/parser/lexer.ts

@@ -26,6 +26,11 @@ export const lexer = (chars: CharStream): Token => {
       break;
     }
 
+    if (!token.hasChars && char === ",") {
+      token.addChar(chars.consumeChar());
+      break;
+    }
+
     if (!token.hasChars && isOpChar(char)) {
       consumeOperator(chars, token);
       break;
@@ -62,6 +67,7 @@ export const lexer = (chars: CharStream): Token => {
 
 const consumeOperator = (chars: CharStream, token: Token) => {
   while (isOpChar(chars.next)) {
+    if (token.value === ">" && chars.next === ">") break; // Ugly hack to support generics, means >> is not a valid operator
     token.addChar(chars.consumeChar());
   }
 };

src/semantics/check-types.ts

@@ -51,7 +51,6 @@ const checkCallTypes = (call: Call): Call | ObjectLiteral => {
   if (call.calls("=")) return checkAssign(call);
   if (call.calls("member-access")) return call; // TODO
   if (call.fn?.isObjectType()) return checkObjectInit(call);
-  call.args = call.args.map(checkTypes);
 
   if (!call.fn) {
     throw new Error(`Could not resolve fn ${call.fnName} at ${call.location}`);
@@ -63,6 +62,8 @@ const checkCallTypes = (call: Call): Call | ObjectLiteral => {
     );
   }
 
+  call.args = call.args.map(checkTypes);
+
   return call;
 };
 
@@ -188,6 +189,16 @@ const checkUse = (use: Use) => {
 };
 
 const checkFnTypes = (fn: Fn): Fn => {
+  if (fn.genericInstances) {
+    fn.genericInstances.forEach(checkFnTypes);
+    return fn;
+  }
+
+  // If the function has type parameters and not genericInstances, it isn't in use and wont be compiled.
+  if (fn.typeParameters) {
+    return fn;
+  }
+
   checkParameters(fn.parameters);
   checkTypes(fn.body);