import { type Entries } from "https://dotland.deno.dev/x/scaffold@0.3.0/src/deps/types.ts";
Many collections have an entries
method which returns an array of a given object's own enumerable string-keyed property [key, value] pairs. The Entries
type will return the type of that collection's entries.
For example the Object
, Map
, Array
, and Set
collections all have this method. Note that WeakMap
and WeakSet
do not have this method since their entries are not enumerable.
Examples
Example 1
Example 1
import type {Entries} from 'type-fest';
interface Example {
someKey: number;
}
const manipulatesEntries = (examples: Entries<Example>) => examples.map(example => [
// Does some arbitrary processing on the key (with type information available)
example[0].toUpperCase(),
// Does some arbitrary processing on the value (with type information available)
example[1].toFixed()
]);
const example: Example = {someKey: 1};
const entries = Object.entries(example) as Entries<Example>;
const output = manipulatesEntries(entries);
// Objects
const objectExample = {a: 1};
const objectEntries: Entries<typeof objectExample> = [['a', 1]];
// Arrays
const arrayExample = ['a', 1];
const arrayEntries: Entries<typeof arrayExample> = [[0, 'a'], [1, 1]];
// Maps
const mapExample = new Map([['a', 1]]);
const mapEntries: Entries<typeof map> = [['a', 1]];
// Sets
const setExample = new Set(['a', 1]);
const setEntries: Entries<typeof setExample> = [['a', 'a'], [1, 1]];