Edouard@3484: /*
Edouard@3484:
Edouard@3484: From https://github.com/keyvan-m-sadeghi/pythonic
Edouard@3484:
Edouard@3484: Slightly modified in order to be usable in browser (i.e. not as a node.js module)
Edouard@3484:
Edouard@3484: The MIT License (MIT)
Edouard@3484:
Edouard@3484: Copyright (c) 2016 Assister.Ai
Edouard@3484:
Edouard@3484: Permission is hereby granted, free of charge, to any person obtaining a copy of
Edouard@3484: this software and associated documentation files (the "Software"), to deal in
Edouard@3484: the Software without restriction, including without limitation the rights to
Edouard@3484: use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
Edouard@3484: the Software, and to permit persons to whom the Software is furnished to do so,
Edouard@3484: subject to the following conditions:
Edouard@3484:
Edouard@3484: The above copyright notice and this permission notice shall be included in all
Edouard@3484: copies or substantial portions of the Software.
Edouard@3484:
Edouard@3484: THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Edouard@3484: IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
Edouard@3484: FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
Edouard@3484: COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
Edouard@3484: IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
Edouard@3484: CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Edouard@3484: */
Edouard@3484:
Edouard@3484: class Iterator {
Edouard@3484: constructor(generator) {
Edouard@3484: this[Symbol.iterator] = generator;
Edouard@3484: }
Edouard@3484:
Edouard@3484: async * [Symbol.asyncIterator]() {
Edouard@3484: for (const element of this) {
Edouard@3484: yield await element;
Edouard@3484: }
Edouard@3484: }
Edouard@3484:
Edouard@3485: forEach(callback) {
Edouard@3485: for (const element of this) {
Edouard@3485: callback(element);
Edouard@3485: }
Edouard@3485: }
Edouard@3485:
Edouard@3484: map(callback) {
Edouard@3484: const result = [];
Edouard@3484: for (const element of this) {
Edouard@3484: result.push(callback(element));
Edouard@3484: }
Edouard@3484:
Edouard@3484: return result;
Edouard@3484: }
Edouard@3484:
Edouard@3484: filter(callback) {
Edouard@3484: const result = [];
Edouard@3484: for (const element of this) {
Edouard@3484: if (callback(element)) {
Edouard@3484: result.push(element);
Edouard@3484: }
Edouard@3484: }
Edouard@3484:
Edouard@3484: return result;
Edouard@3484: }
Edouard@3484:
Edouard@3484: reduce(callback, initialValue) {
Edouard@3484: let empty = typeof initialValue === 'undefined';
Edouard@3484: let accumulator = initialValue;
Edouard@3484: let index = 0;
Edouard@3484: for (const currentValue of this) {
Edouard@3484: if (empty) {
Edouard@3484: accumulator = currentValue;
Edouard@3484: empty = false;
Edouard@3484: continue;
Edouard@3484: }
Edouard@3484:
Edouard@3484: accumulator = callback(accumulator, currentValue, index, this);
Edouard@3484: index++;
Edouard@3484: }
Edouard@3484:
Edouard@3484: if (empty) {
Edouard@3484: throw new TypeError('Reduce of empty Iterator with no initial value');
Edouard@3484: }
Edouard@3484:
Edouard@3484: return accumulator;
Edouard@3484: }
Edouard@3484:
Edouard@3484: some(callback) {
Edouard@3484: for (const element of this) {
Edouard@3484: if (callback(element)) {
Edouard@3484: return true;
Edouard@3484: }
Edouard@3484: }
Edouard@3484:
Edouard@3484: return false;
Edouard@3484: }
Edouard@3484:
Edouard@3484: every(callback) {
Edouard@3484: for (const element of this) {
Edouard@3484: if (!callback(element)) {
Edouard@3484: return false;
Edouard@3484: }
Edouard@3484: }
Edouard@3484:
Edouard@3484: return true;
Edouard@3484: }
Edouard@3484:
Edouard@3484: static fromIterable(iterable) {
Edouard@3484: return new Iterator(function * () {
Edouard@3484: for (const element of iterable) {
Edouard@3484: yield element;
Edouard@3484: }
Edouard@3484: });
Edouard@3484: }
Edouard@3484:
Edouard@3484: toArray() {
Edouard@3484: return Array.from(this);
Edouard@3484: }
Edouard@3484:
Edouard@3484: next() {
Edouard@3484: if (!this.currentInvokedGenerator) {
Edouard@3484: this.currentInvokedGenerator = this[Symbol.iterator]();
Edouard@3484: }
Edouard@3484:
Edouard@3484: return this.currentInvokedGenerator.next();
Edouard@3484: }
Edouard@3484:
Edouard@3484: reset() {
Edouard@3484: delete this.currentInvokedGenerator;
Edouard@3484: }
Edouard@3484: }
Edouard@3484:
Edouard@3484: function rangeSimple(stop) {
Edouard@3484: return new Iterator(function * () {
Edouard@3484: for (let i = 0; i < stop; i++) {
Edouard@3484: yield i;
Edouard@3484: }
Edouard@3484: });
Edouard@3484: }
Edouard@3484:
Edouard@3484: function rangeOverload(start, stop, step = 1) {
Edouard@3484: return new Iterator(function * () {
Edouard@3484: for (let i = start; i < stop; i += step) {
Edouard@3484: yield i;
Edouard@3484: }
Edouard@3484: });
Edouard@3484: }
Edouard@3484:
Edouard@3484: function range(...args) {
Edouard@3484: if (args.length < 2) {
Edouard@3484: return rangeSimple(...args);
Edouard@3484: }
Edouard@3484:
Edouard@3484: return rangeOverload(...args);
Edouard@3484: }
Edouard@3484:
Edouard@3484: function enumerate(iterable) {
Edouard@3484: return new Iterator(function * () {
Edouard@3484: let index = 0;
Edouard@3484: for (const element of iterable) {
Edouard@3484: yield [index, element];
Edouard@3484: index++;
Edouard@3484: }
Edouard@3484: });
Edouard@3484: }
Edouard@3484:
Edouard@3484: const _zip = longest => (...iterables) => {
Edouard@3594: if (iterables.length == 0) {
Edouard@3594: // works starting with 1 iterable
Edouard@3594: // [a,b,c] -> [[a],[b],[c]]
Edouard@3594: // [a,b,c],[d,e,f] -> [[a,d],[b,e],[c,f]]
Edouard@3594: throw new TypeError("zip takes 1 iterables at least, "+iterables.length+" given");
Edouard@3484: }
Edouard@3484:
Edouard@3484: return new Iterator(function * () {
Edouard@3484: const iterators = iterables.map(iterable => Iterator.fromIterable(iterable));
Edouard@3484: while (true) {
Edouard@3484: const row = iterators.map(iterator => iterator.next());
Edouard@3484: const check = longest ? row.every.bind(row) : row.some.bind(row);
Edouard@3484: if (check(next => next.done)) {
Edouard@3484: return;
Edouard@3484: }
Edouard@3484:
Edouard@3484: yield row.map(next => next.value);
Edouard@3484: }
Edouard@3484: });
Edouard@3484: };
Edouard@3484:
Edouard@3484: const zip = _zip(false), zipLongest= _zip(true);
Edouard@3484:
Edouard@3484: function items(obj) {
Edouard@3484: let {keys, get} = obj;
Edouard@3484: if (obj instanceof Map) {
Edouard@3484: keys = keys.bind(obj);
Edouard@3484: get = get.bind(obj);
Edouard@3484: } else {
Edouard@3484: keys = function () {
Edouard@3484: return Object.keys(obj);
Edouard@3484: };
Edouard@3484:
Edouard@3484: get = function (key) {
Edouard@3484: return obj[key];
Edouard@3484: };
Edouard@3484: }
Edouard@3484:
Edouard@3484: return new Iterator(function * () {
Edouard@3484: for (const key of keys()) {
Edouard@3484: yield [key, get(key)];
Edouard@3484: }
Edouard@3484: });
Edouard@3484: }
Edouard@3484:
Edouard@3484: /*
Edouard@3484: module.exports = {Iterator, range, enumerate, zip: _zip(false), zipLongest: _zip(true), items};
Edouard@3484: */