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digitalmars.D.learn - How do I make this function from module public?

reply Jack <jckj33 gmail.com> writes:
I'm playing with wasm, I wrote a small module where I'd like to 
make the function available but wasm can't find this function.

math.d


module math;
extern(C):
int mul(int a, int b) { return a *  b;}


wasm.d



public import math;
extern(C): // disable D mangling
void doSomething() { ... } // seems to be the required entry 
point
void _start() {}


start.html:

<html>
   <head>
     <script>
     (async() => {
         const response = await fetch('wasm.wasm');
         const bytes = await response.arrayBuffer();
         const { instance } = await WebAssembly.instantiate(bytes);
         const res =  instance.exports.mul(2, 4);
         console.log('The answer is: ' + res);
         document.getElementById("result").innerHTML = "The result 
is: " + res;
       })();
     </script>
   </head>
   <body>
     Test page
     <h1 id="result"></h1>
   </body>
</html>

the exported function fails to find 'mul' function, as I can see 
from the browser's console:


start.html:8 Uncaught (in promise) TypeError: 
instance.exports.mul is not a >function at start.html:8


can I make it public using D or do I have to import the wanted 
module with javascript?
Oct 13 2020
next sibling parent Jack <jckj33 gmail.com> writes:
I'm compiling with


 ldc2 -mtriple=wasm32-unknow-unknow-wasm -betterC wasm.d
Oct 13 2020
prev sibling parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Wednesday, 14 October 2020 at 01:46:11 UTC, Jack wrote:

extern(C):
int mul(int a, int b) { return a *  b;}




mark it `export` as well

and then be sure you are compiling in this module as well, it 
must be included on the ldc command line along with wasm.d
Oct 13 2020
parent Jack <jckj33 gmail.com> writes:
On Wednesday, 14 October 2020 at 01:55:13 UTC, Adam D. Ruppe 
wrote:

 On Wednesday, 14 October 2020 at 01:46:11 UTC, Jack wrote:

extern(C):
int mul(int a, int b) { return a *  b;}




 mark it `export` as well

 and then be sure you are compiling in this module as well, it 
 must be included on the ldc command line along with wasm.d


worked, thanks!
Oct 14 2020