Trying to create an array with a size that is a variable imported from the JS doesn't seem to work. For example:
AssemblyScript:
export declare arrSize: u32
const arr = new Uint32Array(arrSize)
export function init (): void {
unchecked(testArr[0]) = 1
store<u32>(0, unchecked(testArr[0]))
}
JS:
const memory = new WebAssembly.Memory({ initial: 1 })
WebAssembly.instantiateStreaming(fetch('module.wasm'), {
env: { memory },
index: { arrSize: 2 }
}).then(module => {
const { init } = module.instance.exports
init()
const arr = new Uint32Array(memory.buffer, 0, 2)
console.log(arr)
})
Whereas if I change const arr = new Uint32Array(2)
in the AssemblyScript file, it works.
Is there a way to have dynamically sized local arrays in the WebAssembly module?
This works:
export declare const count: i32;
const arr = new Array<i32>(count);
export function getCount(): i32 {
return arr.length;
}
And in the imports object for WebAssembly.instantiate
you should have:
{
index: {
count: 22
}
}
provided that you assemblyscript file is named index.ts