README.md

WASM Vulgar References

Like opaque reference types, but...the opposite: https://github.com/WebAssembly/design/blob/master/GC.md#opaque-reference-types

This should give you full access to any JavaScript API including the DOM and Node.js

https://wasdk.github.io/WasmFiddle/?11m3n1

hello_world.c

int main() {
  /* for some reason if I declare these constants outside main(){},
     then the implicit imports of defString/get/set etc stop working */
  const int null = 0;
  const int window = 1;

  int hello_world = jsString("hello world");

  dispose(eval1("log(_)", hello_world));

  int args = eval2("[_0, _1]", jsInt(1), jsInt(2));
  dispose(eval2("_0.push(_1)", args, jsInt(3)));
  dispose(eval2("_0.push(_1)", args, jsInt(4)));
  dispose(eval1("log(_)", args));

  return 0;
}

runtime.js

function str(ptr) {
  return lib.UTF8ArrayToString(new Uint8Array(wasmInstance.exports.memory.buffer), ptr);
}
const WASM_VULGAR_REFS = [null, window];
const empties = [];
function ref(val) {
  const ref = empties.length ? empties.pop() : WASM_VULGAR_REFS.length;
  WASM_VULGAR_REFS[ref] = val;
  return ref;
}
function unref(ref) {
  WASM_VULGAR_REFS[ref] = null;
  empties.push(ref);
}
wasmImports.env = {
  jsInt: ref,
  jsFloat: ref,
  jsString: ptr => ref(str(ptr)),
  jsArray: () => ref([]),
  eval0: expr => ref(new Function('return ' + str(expr))()),
  eval1: (expr, arg) =>
    ref(new Function('_', 'return ' + str(expr))(WASM_VULGAR_REFS[arg])),
  eval2: (expr, arg1, arg2) =>
    ref(new Function('_0', '_1',
      'return ' + str(expr))(WASM_VULGAR_REFS[arg1], WASM_VULGAR_REFS[arg2])),
  dispose: unref,
};
var wasmModule = new WebAssembly.Module(wasmCode);
var wasmInstance = new WebAssembly.Instance(wasmModule, wasmImports);

wasmInstance.exports.main();
window.wasmInstance = wasmInstance