WebAssembly Type Definitions

Type definitions of wasm types and some C types for use in JavaScript.

npm install wasm-types

'Native' WebAssembly Types

// Number types
i32, i64, f32, f64

Extras. You should be able to pass around anyfunc in WebAssembly, not sure about the other two but they are there if you need it.

anyfunc
func
block_type

Utility sizes

The following types are of sizes you can load/set in WebAssembly but are not types. See https://github.com/WebAssembly/spec/tree/master/interpreter#s-expression-syntax

i8, u8, i16, u16, u32
// u64 is special
u64

u64 is not something you can set read in raw WebAssembly but something you can set into memory from JavaScript

sizeof

This module also exports a sizeof lookup Object for convenience.

// In _bytes_
const word = 4;

const sizeof = {
  [i32]: word,
  [i64]: word * 2,
  [f32]: word,
  [f64]: word * 2,
  [u32]: word,
  [u16]: word >> 1,
  [u8]: word >> 2,
  [i8]: word >> 2,
  [i16]: word >> 1,
  [anyfunc]: word,
  [func]: word,
  [block_type]: word
};

Helpers API

Better with curry.

wasmTypes.get(type, index, dataView) -> number

Get a value at index of type from DataView.

wasmTypes.set(type, index, dataView, value) -> void

Set a value at index of type in DataView with value.