NetzoWebAssembly
WebAssembly (abbreviated WASM) is a binary instruction format for the web. It is designed to be a portable target for compilation of higher-level programming languages like C, C++, Rust, Go, Python, AssemblyScript and more, enabling deployment on the web for client and server applications.
WebAssembly is supported by Deno natively with the same web APIs used accross browsers. This can be leveraged to write performant, low-level code that can be compiled to WebAssembly and run in the browser.
The following examples demonstrate how to use WebAssembly with Netzo. The source code for these examples is the following Rust program exporting a single function main which returns the number 42:
pub fn main() -> u32 {
42
}pub fn main() -> u32 {
42
}Load from byte Array
const wasmCode = new Uint8Array([
0, 97, 115, 109, 1, 0, 0, 0, 1, 133, 128, 128, 128, 0, 1, 96, 0, 1, 127,
3, 130, 128, 128, 128, 0, 1, 0, 4, 132, 128, 128, 128, 0, 1, 112, 0, 0,
5, 131, 128, 128, 128, 0, 1, 0, 1, 6, 129, 128, 128, 128, 0, 0, 7, 145,
128, 128, 128, 0, 2, 6, 109, 101, 109, 111, 114, 121, 2, 0, 4, 109, 97,
105, 110, 0, 0, 10, 138, 128, 128, 128, 0, 1, 132, 128, 128, 128, 0, 0,
65, 42, 11
])
const wasmModule = new WebAssembly.Module(wasmCode)
const wasmInstance = new WebAssembly.Instance(wasmModule)
const main = wasmInstance.exports.main as CallableFunction
console.log(main().toString()) // 42const wasmCode = new Uint8Array([
0, 97, 115, 109, 1, 0, 0, 0, 1, 133, 128, 128, 128, 0, 1, 96, 0, 1, 127,
3, 130, 128, 128, 128, 0, 1, 0, 4, 132, 128, 128, 128, 0, 1, 112, 0, 0,
5, 131, 128, 128, 128, 0, 1, 0, 1, 6, 129, 128, 128, 128, 0, 0, 7, 145,
128, 128, 128, 0, 2, 6, 109, 101, 109, 111, 114, 121, 2, 0, 4, 109, 97,
105, 110, 0, 0, 10, 138, 128, 128, 128, 0, 1, 132, 128, 128, 128, 0, 0,
65, 42, 11
])
const wasmModule = new WebAssembly.Module(wasmCode)
const wasmInstance = new WebAssembly.Instance(wasmModule)
const main = wasmInstance.exports.main as CallableFunction
console.log(main().toString()) // 42Load from file
const wasmCode = await Deno.readFile('main.wasm')
const wasmModule = new WebAssembly.Module(wasmCode)
const wasmInstance = new WebAssembly.Instance(wasmModule)
const main = wasmInstance.exports.main as CallableFunction
console.log(main().toString()) // 42const wasmCode = await Deno.readFile('main.wasm')
const wasmModule = new WebAssembly.Module(wasmCode)
const wasmInstance = new WebAssembly.Instance(wasmModule)
const main = wasmInstance.exports.main as CallableFunction
console.log(main().toString()) // 42Load from URL
The .wasm file must be served with "application/wasm" MIME type
const { instance, module } = await WebAssembly.instantiateStreaming(
fetch('https://wpt.live/wasm/incrementer.wasm'),
)
const increment = instance.exports.increment as (input: number) => number
console.log(increment(41)) // 42const { instance, module } = await WebAssembly.instantiateStreaming(
fetch('https://wpt.live/wasm/incrementer.wasm'),
)
const increment = instance.exports.increment as (input: number) => number
console.log(increment(41)) // 42