Why any number value can be used in interface member declared with enum literal type?

user_3459704 0
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I have the following typescript enum:

enum Status {
    READY = 0,
    FAILED = 1
}

and the following interface:

interface ReadyItem {
    id: number;
    status: Status.READY;
}

Why am I able to redeclare the value of status in the following case?

const readyItem: ReadyItem = {
    id: 1,
    status: 58 // no error here
}

If I change my enum number values to string values, it works as intended:

enum Status {
    READY = "ready",
    FAILED = "failed"
}

interface ReadyItem {
    id: number;
    status: Status.READY;
}

const readyItem = {
    id: 1,
    status: 'other' // error: Type 'other' is not assignable to type 'Status.READY'.
}

Can someone tell me how I can have this behavior with number values?

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typescript
1 Answers

I think it should be

...
interface ReadyItem {
    id: number;
    status: Status;
}
...

Now you're constraining status prop to accept only one value from enum

user_104513640
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