j100002ben · October 5, 2020 15:10 · Oct 4, 2020 · Oct 4, 2020 · Oct 4, 2020
diff --git a/app-tinygo.js b/app-tinygo.js
@@ -0,0 +1,41 @@
+import 'vendor/tinygo'
+
+const go = new Go();
+
+go.importObject.env['main.defineClass'] = function(namePtr, nameLen, cPtr, cGcPtr, pPtr/*, pGcPtr*/) {
+  const mem = new DataView(go._inst.exports.memory.buffer)
+  const decoder = new TextDecoder("utf-8");
+
+  const name = decoder.decode(new DataView(go._inst.exports.memory.buffer, namePtr, nameLen));
+  const constructorID = mem.getUint32(cPtr, true)
+  const constructor = go._values[constructorID]
+
+  const prototypeID = mem.getUint32(pPtr, true)
+  const prototypes = go._values[prototypeID]
+
+  window[name] = (new Function(
+    'constructor', 'prototypes',
+    `
+      function ${name}() {
+        if(!(this instanceof ${name})) {
+          throw new TypeError("Cannot call a class as a function")
+        }
+
+        return constructor.apply(this, arguments)
+      }
+
+      prototypes.call(${name}.prototype)
+
+      return ${name}
+    `
+  ))(constructor, prototypes);
+}
+
+WebAssembly
+  .instantiateStreaming(
+    fetch(require('./main.wasm')),
+    go.importObject,
+  )
+  .then(result => {
+    go.run(result.instance);
+  });
diff --git a/app.js b/app.js
@@ -1,17 +1,41 @@
-import 'vendor/tinygo'
+import 'vendor/golang'
 
 const go = new Go();
 
-go.importObject.env['main.defineClass'] = function(namePtr, nameLen, cPtr, cGcPtr, pPtr/*, pGcPtr*/) {
-  const mem = new DataView(go._inst.exports.memory.buffer)
-  const decoder = new TextDecoder("utf-8");
+const decoder = new TextDecoder("utf-8");
 
-  const name = decoder.decode(new DataView(go._inst.exports.memory.buffer, namePtr, nameLen));
-  const constructorID = mem.getUint32(cPtr, true)
-  const constructor = go._values[constructorID]
+const getInt64 = (mem, addr) => {
+  const low = mem.getUint32(addr + 0, true);
+  const high = mem.getInt32(addr + 4, true);
+  return low + high * 4294967296;
+}
+
+const loadString = (mem, addr) => {
+  const saddr = getInt64(mem, addr + 0);
+  const len = getInt64(mem, addr + 8);
+  return decoder.decode(new DataView(mem.buffer, saddr, len));
+}
+
+const loadValue = (mem, addr) => {
+  const f = mem.getFloat64(addr, true);
+  if (f === 0) {
+    return undefined;
+  }
+  if (!isNaN(f)) {
+    return f;
+  }
+
+  const id = mem.getUint32(addr, true);
+  return go._values[id];
+}
+
+go.importObject.go['main.defineClass'] = function(sp) {
+  const mem = new DataView(go._inst.exports.mem.buffer)
+
+  const name = loadString(mem, sp + 8);
 
-  const prototypeID = mem.getUint32(pPtr, true)
-  const prototypes = go._values[prototypeID]
+  const constructor = loadValue(mem, sp + 24)
+  const prototypes = loadValue(mem, sp + 40)
 
   window[name] = (new Function(
     'constructor', 'prototypes',

diff --git a/main_js.s b/main_js.s
@@ -0,0 +1,5 @@
+#include "textflag.h"
+
+TEXT ·defineClass(SB), NOSPLIT, $0
+  CallImport
+  RET
diff --git a/app.js b/app.js
@@ -2,34 +2,33 @@ import 'vendor/tinygo'
 
 const go = new Go();
 
-go.importObject.env['main.defineClass'] = function(namePtr, nameLen, funcAddr) {
+go.importObject.env['main.defineClass'] = function(namePtr, nameLen, cPtr, cGcPtr, pPtr/*, pGcPtr*/) {
   const mem = new DataView(go._inst.exports.memory.buffer)
   const decoder = new TextDecoder("utf-8");
 
   const name = decoder.decode(new DataView(go._inst.exports.memory.buffer, namePtr, nameLen));
-  const f = mem.getFloat64(funcAddr, true)
-  if (f === 0) {
-    throw new TypeError("Constructor not defined")
-  }
-  if(!isNaN(f)) {
-    throw new TypeError("Constructor not defined")
-  }
+  const constructorID = mem.getUint32(cPtr, true)
+  const constructor = go._values[constructorID]
 
-  const id = mem.getUint32(funcAddr, true)
-  const constructor = go._values[id]
+  const prototypeID = mem.getUint32(pPtr, true)
+  const prototypes = go._values[prototypeID]
 
   window[name] = (new Function(
-    'constructor',
+    'constructor', 'prototypes',
     `
-      return function ${name}() {
+      function ${name}() {
         if(!(this instanceof ${name})) {
           throw new TypeError("Cannot call a class as a function")
         }
 
         return constructor.apply(this, arguments)
       }
+
+      prototypes.call(${name}.prototype)
+
+      return ${name}
     `
-  ))(constructor);
+  ))(constructor, prototypes);
 }
 
 WebAssembly

diff --git a/main.go b/main.go
@@ -2,13 +2,23 @@ package main
 
 func defineClass(name string, constructor js.Value)
 
+func pointGetX(this js.Value, []inputs js.Value) interface{} {
+  return this.Get("x") 
+}
+
 func pointConstructor(this js.Value, []inputs js.Value) interface{} {
   this.Set("x", inputs[0])
   this.Set("y", inputs[1])
 
   return this; 
 }
 
+func pointPrototype(this js.Value, []inputs js.Value) interface{} {
+  this.Set("getX", js.FuncOf(pointGetX))
+
+  return nil
+}
+
 func main() {
   defineClass("Point", js.FuncOf(pointConstructor).Value)
 

diff --git a/app.js b/app.js
@@ -0,0 +1,42 @@
+import 'vendor/tinygo'
+
+const go = new Go();
+
+go.importObject.env['main.defineClass'] = function(namePtr, nameLen, funcAddr) {
+  const mem = new DataView(go._inst.exports.memory.buffer)
+  const decoder = new TextDecoder("utf-8");
+
+  const name = decoder.decode(new DataView(go._inst.exports.memory.buffer, namePtr, nameLen));
+  const f = mem.getFloat64(funcAddr, true)
+  if (f === 0) {
+    throw new TypeError("Constructor not defined")
+  }
+  if(!isNaN(f)) {
+    throw new TypeError("Constructor not defined")
+  }
+
+  const id = mem.getUint32(funcAddr, true)
+  const constructor = go._values[id]
+
+  window[name] = (new Function(
+    'constructor',
+    `
+      return function ${name}() {
+        if(!(this instanceof ${name})) {
+          throw new TypeError("Cannot call a class as a function")
+        }
+
+        return constructor.apply(this, arguments)
+      }
+    `
+  ))(constructor);
+}
+
+WebAssembly
+  .instantiateStreaming(
+    fetch(require('./main.wasm')),
+    go.importObject,
+  )
+  .then(result => {
+    go.run(result.instance);
+  });
diff --git a/main.go b/main.go
@@ -0,0 +1,17 @@
+package main
+
+func defineClass(name string, constructor js.Value)
+
+func pointConstructor(this js.Value, []inputs js.Value) interface{} {
+  this.Set("x", inputs[0])
+  this.Set("y", inputs[1])
+
+  return this; 
+}
+
+func main() {
+  defineClass("Point", js.FuncOf(pointConstructor).Value)
+
+  // Keep Golang running
+  <-make(chan bool)
+}