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typescriptiteratorsymbols

Symbol.iterator for enum values in Typescript

I would like to use the Symbol.iterator for an enum to iterate over its values like this:

enum Color {red, green, blue}

Color[Symbol.iterator] = function*():Iterator<Color> {
        yield Color.red;
        yield Color.green;
        yield Color.blue;
    }

for (let color of Color){
 alert(color);
}

But this does not work. What will work? Most important for me is not having to change the for/of line.

The error I got on the for/of line: TS2488: Type must have a 'Symbol.iterator' method that returns an iterator.

Solution

  • The closest I can get is:

    enum Color {red, green, blue}

module Color 
{
    export function* Values() 
    {
        yield Color.red;
        yield Color.green;
        yield Color.blue;
    }
}

for (let color of Color.Values())
{
    alert(color);
}

    Although it does slightly modifies your for/of loop. Hopefully it will be of any help to you.