import example

README.md

@@ -13,6 +13,7 @@ config    /home/e/.dlang/etc/ldc2.conf (x86_64-unknown-linux-gnu)
 
 
 ldc2 -mtriple=wasm32-unknown-unknown-wasm -O --betterC add_two.d
+ldc2 -mtriple=wasm32-unknown-unknown-wasm -O -L-allow-undefined --betterC add_two.d
 
 
 $ ls -alh add_two.wasm

add_two.d

@@ -1,7 +1,10 @@
 
 extern(C): // disable D mangling
 
+void print(int a);
+
 int add_two(int a, int b){
+  print(a + b);
   return a + b;
 }
 

index.html

@@ -15,7 +15,9 @@ function test1(ex){
 }
 
 window.addEventListener("load", function(){
-  var env = { env: {} };
+  var env = { env: {
+    print: (result) => { console.log('result = ', result); }
+  } };
   WebAssembly.instantiateStreaming( fetch('add_two.wasm'), env).then( result => {
     console.log('WASM loaded!');
     var ex = result.instance.exports;