Can't iterate over (U)Int8Array, (U)Int16Array, (U)Int32Array, etc. using for ... of

[SetTrend]

This small piece of code doesn't compile:

const bytes = new Uint8Array(8);
window.crypto.getRandomValues(bytes);
for (const byte of bytes) { }

This is the error that's being generated:

C:\Temp>node tsc test.ts
test.ts(5,20): error TS2495: Type 'Uint8Array' is not an array type or a string type.

[andru255]

@SetTrend By default Typescript allows types number, boolean, string, any. Please See: https://www.typescriptlang.org/docs/handbook/basic-types.html
But you can create a little bit custom types with interfaces:
https://www.typescriptlang.org/docs/handbook/interfaces.html
I'm in the way to learn more about typescript too

[yortus]

Sounds like you are targeting ES5, for which TypeScript offers limited for..of support. There are related issue about this, like #4947, #6842, #5329, and #3164.

[SetTrend]

Thanks, @yortus, for your enlightening answer.

I believe #3164 gets closest to what I would have imagined for having targetted ES5.

Are there plans to have for ... of get this functionality for ES5, too? I am forced to target IE11 at many corporated places.

[yortus]

@SetTrend I couldn't speak for what the TypeScript team's plans are, but looking at the comments in those linked issues (and also in #4031), there seems to be some sympathy for users but no concrete plans.

[mhegazy]

This should be addressed by #12346 under --downlevelIteration. Make sure es2015.iterable is part of your --lib arguments.