es-toolkit/dist/fp/array/uniq.js

A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.

const require_uniq = require("../../array/uniq.js");
const require_lazy = require("../_internal/lazy.js");
//#region src/fp/array/uniq.ts
/**
* Creates a function that removes duplicate values from an array, preserving
* the order of first occurrence. Equality follows SameValueZero, matching
* Set semantics. Use it with {@link pipe}.
*
* The returned function is lazy-capable inside {@link pipe}. It keeps a Set of
* values already emitted during each pipeline run.
*
* @template T - The type of elements in the array.
* @returns A function that maps a readonly array to a duplicate-free array.
*
* @example
* import { pipe, uniq } from 'es-toolkit/fp';
*
* pipe([1, 2, 2, 3, 3, 3], uniq());
* // => [1, 2, 3]
*/
function uniq() {
	function uniqEager(array) {
		return require_uniq.uniq(array);
	}
	const uniqLazy = (emit) => {
		const seen = /* @__PURE__ */ new Set();
		return (value) => {
			if (seen.has(value)) return true;
			seen.add(value);
			return emit(value);
		};
	};
	return require_lazy.combineEagerAndLazyFunctions(uniqEager, uniqLazy);
}
//#endregion
exports.uniq = uniq;