pass the data from js to wasm

zhentian-wan · Oct 20, 2018 · ae646a6 · ae646a6
1 parent fa525c6
commit ae646a6
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Showing 3 changed files with 34 additions and 2 deletions.
diff --git a/index.html b/index.html
@@ -2,12 +2,31 @@
 <html>
   <head>
     <script> 
-      WebAssembly.instantiateStreaming(fetch("utils.gc.wasm"))
+
+      // pass the data from Js to Rust
+      const appendNumberToBody = (number) => {
+        const text = document.createTextNode(number);
+        document.body.appendChild(text);
+      }
+
+      const importObject = {
+        env: {
+          appendNumberToBody: appendNumberToBody,
+          alert: alert
+        }
+      };
+
+      WebAssembly.instantiateStreaming(fetch("utils.gc.wasm"), importObject)
+      .then(wasmModule => {
+          wasmModule.instance.exports.run();
+        });
+
+      /*WebAssembly.instantiateStreaming(fetch("utils.gc.wasm"))
         .then(wasmModule => {
           const result = wasmModule.instance.exports.add_one(3);
           const text = document.createTextNode(result);
           document.body.appendChild(text);
-        });
+        });*/
     </script>
   <head>
   <body></body>

diff --git a/src/lib.rs b/src/lib.rs
@@ -1,4 +1,17 @@
 #[no_mangle]
 pub extern fn add_one(x: u32) -> u32 {
     x + 1
+}
+
+extern {
+    fn appendNumberToBody(x: u32);
+    fn alert(x: u32);
+}
+
+#[no_mangle]
+pub extern fn run() {
+    unsafe {
+        appendNumberToBody(42);
+        alert(33)
+    }
 }
diff --git a/utils.gc.wasm b/utils.gc.wasm