How Is 'this' Used In A Function And Is It Required?

We're trying to convert the function PSRunner to a TypeScript function: export function PSRunner(commands: string[]) { const self: { out: string[] err: string[] } = thi

Solution 1:

Regarding the question about any, I wouldn't expect that to cause an actual error (by which I mean it won't transpile due to syntax errors), but I would expect a linter plugin to be complaining about it.

In general, you want to either use unknown instead of any if what you really mean is "I won't know until runtime what object actually gets bound to this type", because any will be far too lenient in letting you reference members that may or may not exist, whereas unknown is a little more strict (and type-safe).

Before resorting to unknown however, it's generally preferable to define an actual type, even something like Record<string, string> (an object with string properties mapping to string values). Or using a generic type if you need something a little more dynamic (although, not the case here).

In fact, recently typescript made a change where a caught exception is promoted to be unknown as opposed to the former any, due to type safety. https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-0.html#unknown-on-catch-clause-bindings

In general, avoid any, and any good linter will tell you the same. I assume that's what your error was about. Correct me if I was mistaken, though.