bfwasm's Introduction

bfwasm

A non-optimizing Brainf_ck to WebAssembly compiler. Yes, compiler. Not interpreter.

Installation

npm install -g @surma/bfwasm

Usage (CLI)

Usage: bfwasm [options]

Options:
  -o, --output <file>  File to write compiled Wasm to
  -r, --run            Run compiled Wasm (implies --asyncify)
  --mem-dump <N>       Dump the first N cells of memory after run
  --hex-output         Turn std out into hexadecimap
  --asyncify           Run Binaryen Asyncify pass
  --wasi               Use WASI for I/O
  -h, --help           output usage information

Usage (API)

import { compile } from "@surma/bfwasm";

const wasmBuffer = compile(`
  ++++++++++[>++++++++++++++++++++++
  >+++++++++++++++>++++++++++++++++>+
  <<<<-]>++++++.>+++++++.>++++.
`);

const decoder = new TextDecoder();
const importsObj = {
  env: {
    in() {
      /* Called when bf programm needs input */
      return 0;
    },
    out(v) {
      /* Called when bf programm has output */
      console.log(
        decoder.decode(new Uint8Array([v]), {stream: true})
      );
    }
  }
};
const {instance} = await WebAssembly.instantiate(wasmBuffer, importsObj);
instance.exports._start();

compile(program, options) compiles program to a WebAssembly module exporting a "_start" function.

Options:

exportMemory (default: true) will export the memory as "memory".
autoRun (default: false) will declare "_start" as the module’s start function.
useWasi (default: false) use WASI core for I/O.