remeda
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A utility library for JavaScript and Typescript.
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text/typescript
import { IterableContainer } from "./IterableContainer-JENOIFLG.cjs";
import { BoundedPartial } from "./BoundedPartial-Dk-WxpZ7.cjs";
import { Simplify } from "type-fest";
//#region src/fromKeys.d.ts
type ExactlyOneKey<T, V> = T extends PropertyKey ? Record<T, V> : never;
type FromKeys<T extends IterableContainer, V> = T extends readonly [] ? {} : T extends readonly [infer Head, ...infer Rest] ? ExactlyOneKey<Head, V> & FromKeys<Rest, V> : T[number] extends PropertyKey ? BoundedPartial<Record<T[number], V>> : never;
/**
* Creates an object that maps each key in `data` to the result of `mapper` for
* that key. Duplicate keys are overwritten, guaranteeing that `mapper` is run
* for each item in `data`.
*
* There are several other functions that could be used to build an object from
* an array:
* * `indexBy` - Builds an object from an array of *values* and a mapper for keys.
* * `pullObject` - Builds an object from an array of items with mappers for *both* keys and values.
* * `fromEntries` - Builds an object from an array of key-value pairs.
* Refer to the docs for more details.
*
* @param data - An array of keys of the output object. All items in the array
* would be keys in the output array.
* @param mapper - Takes a key and returns the value that would be associated
* with that key.
* @signature
* R.fromKeys(data, mapper);
* @example
* R.fromKeys(["cat", "dog"], R.length()); // { cat: 3, dog: 3 } (typed as Partial<Record<"cat" | "dog", number>>)
* R.fromKeys([1, 2], R.add(1)); // { 1: 2, 2: 3 } (typed as Partial<Record<1 | 2, number>>)
* @dataFirst
* @category Object
*/
declare function fromKeys<T extends IterableContainer<PropertyKey>, V>(data: T, mapper: (item: T[number], index: number, data: T) => V): Simplify<FromKeys<T, V>>;
/**
* Creates an object that maps each key in `data` to the result of `mapper` for
* that key. Duplicate keys are overwritten, guaranteeing that `mapper` is run
* for each item in `data`.
*
* There are several other functions that could be used to build an object from
* an array:
* * `indexBy` - Builds an object from an array of *values* and a mapper for keys.
* * `pullObject` - Builds an object from an array of items with mappers for *both* keys and values.
* * `fromEntries` - Builds an object from an array of key-value pairs.
* Refer to the docs for more details.
*
* @param mapper - Takes a key and returns the value that would be associated
* with that key.
* @signature
* R.fromKeys(mapper)(data);
* @example
* R.pipe(["cat", "dog"], R.fromKeys(R.length())); // { cat: 3, dog: 3 } (typed as Partial<Record<"cat" | "dog", number>>)
* R.pipe([1, 2], R.fromKeys(R.add(1))); // { 1: 2, 2: 3 } (typed as Partial<Record<1 | 2, number>>)
* @dataLast
* @category Object
*/
declare function fromKeys<T extends IterableContainer<PropertyKey>, V>(mapper: (item: T[number], index: number, data: T) => V): (data: T) => Simplify<FromKeys<T, V>>;
//#endregion
export { fromKeys };
//# sourceMappingURL=fromKeys-DZMu-mA7.d.cts.map