Type aliases

[Naddiseo]

This really depends on how deeply the type hinting is. If the hint is just the superficial/toplevel/boxed/primitive type, then aliases aren't really needed. However, if anything further is allowed, then I think aliases would definitely be helpful, especially with callback functions.

[lukescott]

I'm not sure if aliases are needed. And they somewhat already exist is ES6 import:

import {AliasFoo as default} from "foo";

function doSomethingWithAliasFoo(foo AliasFoo) {...}

[Naddiseo]

As mentioned in #4, If TypeHint is a LeftHandSideExpression then a type alias can be boiled down to:

const AliasType = OtherType;

And if types are then stripped out after checking, the aliases should also be removed by inlining and dead-code elimination.

[Naddiseo]

Let's leave this out for now. If developers and tool creators want this feature, then we can revisit the issue.