IterableHelpers.js
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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
/**
* @template T
* @param {Iterable<T>} set a set
* @returns {T | undefined} last item
*/
const last = set => {
let last;
for (const item of set) last = item;
return last;
};
/**
* @template T
* @param {Iterable<T>} iterable iterable
* @param {function(T): boolean} filter predicate
* @returns {boolean} true, if some items match the filter predicate
*/
const someInIterable = (iterable, filter) => {
for (const item of iterable) {
if (filter(item)) return true;
}
return false;
};
/**
* @template T
* @param {Iterable<T>} iterable an iterable
* @returns {number} count of items
*/
const countIterable = iterable => {
let i = 0;
// eslint-disable-next-line no-unused-vars
for (const _ of iterable) i++;
return i;
};
exports.last = last;
exports.someInIterable = someInIterable;
exports.countIterable = countIterable;