typescript enum string type an array of Object.keys

Question

Is there a stricter way of typing

an array build with Object.keys ?

I mean instead using string[]

sort of (key in Languages)[] ?

export enum Languages {
    de = 'de',
    en = 'en',
    fr = 'fr'
}

const langs: string[] = Object.keys(Languages);

Just a side note: enum names are usually singular rather than plural, e.g. Language rather than Languages. — T.J. Crowder
– T.J. Crowder, Commented Dec 14, 2019 at 13:03

T.J. Crowder · Accepted Answer · 2019-12-14 13:01:26Z

2

Object.keys is defined as returning string[] because it needs to be defined to handle the general case.

In your specific case, you can use a type assertion on the value keys returns:

const langs = Object.keys(Languages) as Languages[];

answered Dec 14, 2019 at 13:01

T.J. Crowder

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