UNPKG

type-fest/source/string-key-of.d.ts

Version:

506 BTypeScriptView Raw

1/**
2Get keys of the given type as strings.
3
4Number keys are converted to strings.
5
6Use-cases:
7- Get string keys from a type which may have number keys.
8- Makes it possible to index using strings retrieved from template types.
9
10@example
11```
12import type {StringKeyOf} from 'type-fest';
13
14type Foo = {
15	1: number,
16	stringKey: string,
17};
18
19type StringKeysOfFoo = StringKeyOf<Foo>;
20//=> '1' | 'stringKey'
21```
22
23@category Object
24*/
25export type StringKeyOf<BaseType> = `${Extract<keyof BaseType, string | number>}`;

1	`/**`
2	`Get keys of the given type as strings.`
3
4	`Number keys are converted to strings.`
5
6	`Use-cases:`
7	`- Get string keys from a type which may have number keys.`
8	`- Makes it possible to index using strings retrieved from template types.`
9
10	`@example`
11	```
12	`import type {StringKeyOf} from 'type-fest';`
13
14	`type Foo = {`
15	`1: number,`
16	`stringKey: string,`
17	`};`
18
19	`type StringKeysOfFoo = StringKeyOf<Foo>;`
20	`//=> '1' \| 'stringKey'`
21	```
22
23	`@category Object`
24	`*/`
25	export type StringKeyOf<BaseType> = `${Extract<keyof BaseType, string \| number>}`;