mischnic / parcel-plugin-emscripten

📦 Import C(++) files with Parcel

Parcel plugin for Emscripten

A Parcel plugin to enable importing a C(++) file inside a JS file.

Emscripten has to be installed and emcc needs to be in PATH.

Example:

import Module from './test.c';
const Instance = Module();

Instance.then(()=>{
    console.log(Instance._add(10,20));
});

// equivalent to

Instance.then((v)=>{
    console.log(v._add(10,20));
});

//test.c
#include <emscripten.h>

int EMSCRIPTEN_KEEPALIVE add(int x, int y) {
    return x + y;
}

For more complex examples, see the example directory.

Instance.then is quite fragile and not a thenable, see emscripten-core/emscripten#5820

Using multiple Modules (= importing multiple C files) is supported, but it isn't very filesize efficient. Consider writing a single C-wrapper and importing that instead!

To pass additional arguments to emcc (change optimization, link another C file or a library, ...), specify them in the first line of your main C file: (this would disable optimizations and compile and link lib.c as well)

//parcel: -O0 lib.c
#include ...

parcel-plugin-emscripten's Issues

Doesn't work on Windows due to lack of PATHEXT support

On Windows we need to call emcc.bat instead of emcc. Node doesn't respect PATHEXT so doesn't do this automatically. This plugin should probably do something like process.platform === 'win32' ? 'emcc.bat' : 'emcc'. Current behaviour is ENOENT.