v4ul7io / assemblyscript

A TypeScript to WebAssembly compiler 🚀

AssemblyScript

AssemblyScript compiles strictly typed TypeScript to WebAssembly using Binaryen. It generates lean and mean WebAssembly modules while being just an npm install away.

See the AssemblyScript wiki for further instructions and documentation. You can also try it out in WebAssembly Studio!

Examples

A few early examples to get an idea:

• Conway's Game of Life
  Continuously updates the cellular automaton and visualizes its state on a canvas.

• i64 polyfill
  Exposes WebAssembly's i64 operations to JavaScript using 32-bit integers (low and high bits).

• PSON decoder
  A simple decoder for the PSON binary format.

• WASM parser
  A WebAssembly binary parser in WebAssembly.

Or browse the compiler tests for a more in-depth overview of what's supported already. One of them is a showcase.

Installation

Note that this version of the compiler is relatively new and that some features a TypeScript programmer might expect are still in the works (see also: Limitations). Therefore, it's not on npm, yet, but you can already try it out today:

$> git clone https://github.com/AssemblyScript/assemblyscript.git
$> cd assemblyscript
$> npm install
$> npm link

Alternatively, it's also possible to point npm to the GitHub repository for now:

$> npm install AssemblyScript/assemblyscript

Afterwards, once your project is configured, it's just a matter of using your existing TypeScript tooling while coding, and running the CLI to build to WebAssembly:

$> asc myModule.ts -o myModule.wasm --optimize --validate --sourceMap

Building

To build an UMD bundle to dist/assemblyscript.js (depends on binaryen.js):

$> npm run build

This also builds a browser version of asc to dist/asc.js (depends on assemblyscript.js).

Running the tests:

$> npm test

Note that freshly cloned copies of the compiler will use the distribution files, but it can also run the sources directly through ts-node after an npm run clean, which is useful in development. This condition can also be checked by running asc -v (it is running the sources if it states -dev).