Can you define string length in TypeScript interfaces?

Question

I have a struct like so:

struct tTest{
  char foo [1+1];
  char bar [64];
};

In TypesScript I have

export interface tTest{
  foo: string;
  bar: string;
}

Is there a way to add [64] and [1+1] to the type?

Answer 1

As the comments say: js/ts don't support the char type and there's no way to declare array/string lengths.

You can enforce that using a setter though:

interface tTest {
    foo: string;
}

class tTestImplementation implements tTest {
    private _foo: string;

    get foo(): string {
        return this._foo;
    }

    set foo(value: string) {
        this._foo = value;

        while (this._foo.length < 64) {
            this._foo += " ";
        }
    }
}

(code in playground)

You'll need to have an actual class as the interfaces lacks implementation and doesn't survive the compilation process.
I just added spaces to get to the exact length, but you can change that to fit your needs.