# iterable-query > Query library for ECMAScript iterables. Latest version **1.0.0-pre.16** (published 2019-06-25) · Apache-2.0 license · 0 weekly downloads ## Install ```sh npm install iterable-query pnpm add iterable-query yarn add iterable-query bun add iterable-query ``` ## Health **Score 25/100 (F)** — status: abandoned. Positive: has types; no vulnerabilities; high quality score. Warnings: low downloads; no esm support; large bundle. Negative: abandoned; low maintenance score. ## Facts | | | |---|---| | Version | 1.0.0-pre.16 | | Published | 2019-06-25 | | First published | 2016-04-25 | | Weekly downloads | 0 | | License | Apache-2.0 | | TypeScript types | bundled | | Module format | CommonJS | | Dependencies | 5 | | Unpacked size | 14.4 MB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 71 | | Author | Ron Buckton | | Maintainers | rbuckton | | Keywords | query, iterator, iterable, zip, map, filter, reduce, order, hierarchy | ## Links - npm: https://www.npmjs.com/package/iterable-query - Repository: https://github.com/rbuckton/iterable-query - Issues: https://github.com/rbuckton/iterable-query/issues - npm.io page: https://npm.io/package/iterable-query ## Dependencies (5) - [tslib](https://npm.io/package/tslib.md) ^1.9.3 - [@esfx/equatable](https://npm.io/package/@esfx/equatable.md) ^1.0.0-pre.9 - [@esfx/collection-core](https://npm.io/package/@esfx/collection-core.md) ^1.0.0-pre.11 - [@esfx/collections-hashmap](https://npm.io/package/@esfx/collections-hashmap.md) ^1.0.0-pre.11 - [@esfx/collections-hashset](https://npm.io/package/@esfx/collections-hashset.md) ^1.0.0-pre.11 ## Alternatives - [gamedig](https://npm.io/package/gamedig.md) — 29.3K weekly downloads - [join-monster](https://npm.io/package/join-monster.md) — 12.8K weekly downloads - [masked](https://npm.io/package/masked.md) — 5.5K weekly downloads - [@comunica/actor-query-process-explain-logical](https://npm.io/package/@comunica/actor-query-process-explain-logical.md) — 4.7K weekly downloads - [@veracity/vui](https://npm.io/package/@veracity/vui.md) — 4.6K weekly downloads ## Recent versions - 1.0.0-pre.16 (latest) — 2019-06-25 - 1.0.0-pre.0 (next) — 2018-10-08 - 1.0.0-pre.15 — 2019-03-30 - 1.0.0-pre.14 — 2019-03-25 - 1.0.0-pre.13 — 2018-11-27 - 1.0.0-pre.12 — 2018-11-22 - 1.0.0-pre.11 — 2018-11-15 - 1.0.0-pre.10 — 2018-11-09 - 1.0.0-pre.9 — 2018-11-07 - 1.0.0-pre.8 — 2018-11-07 - 1.0.0-pre.7 — 2018-11-06 - 1.0.0-pre.6 — 2018-11-05 - 1.0.0-pre.5 — 2018-11-02 - 1.0.0-pre.4 — 2018-10-26 - 1.0.0-pre.3 — 2018-10-24 - … 7 more at https://npm.io/package/iterable-query/versions ## README # iterable-query - Query API for JavaScript Iterables and Async Iterables ```ts // TypeScript import { Query } from "iterable-query"; // JavaScript (CommonJS) const { Query } = require("iterable-query"); let q = Query .from(books) .filter(book => book.author === "Alice") .groupBy(book => book.releaseYear); // TypeScript (functional style) import { filter, groupBy } from "iterable-query/fn"; // JavaScript (functional style, CommonJS) const { filter, groupBy } = require("iterable-query/fn") let i = groupBy( filter(books, book => book.author === "Alice"), book => book.releaseYear); ``` **iterable-query** is a library that provides a query API for ES6 iterables, adding numerous operations found in other languages like Haskell, Scala, and C# (.NET). ## Installing For the latest version: ```cmd npm install iterable-query ``` ## Documentation * [API Reference](https://rbuckton.github.io/iterable-query/modules/_iterable_query_.html) ## Examples ### Filtering ```ts let gen = function*() { yield 1; yield 2; yield 3; }; let evens = Query .from(gen()) .filter(i => i % 2 === 0); let odds = Query .from(gen()) .where(i => i % 2 === 1); // alias for `filter` ``` ### Sorting ```ts let books = [ { id: 1, title: "QueryJS a query API for JavaScript", author: "Smith, David" }, { id: 2, title: "Iterators and You", author: "Smith, Bob" }, { id: 3, title: "All the Queries", author: "Smith, Frank" } ] let ordered = Query .from(books) .orderBy(book => book.title) .thenBy(book => book.author); let result = [...ordered]; ``` ### Grouping ```ts let groups = [ { id: 1, name: "Admin" }, { id: 2, name: "Standard User" } ]; let users = [ { id: 1, name: "Bob", groupId: 2 }, { id: 2, name: "Alice", groupId: 1 }, { id: 3, name: "Tom", groupId: 2 } ]; let usersByGroup = Query .from(groups) .groupJoin(users, group => group.id, user => user.id); for (let groupUsers of usersByGroup) { print(groupUsers.key); print('======'); for (let user of groupUsers) { print(user.name); } } ``` ### Hierarchies ```ts let doc = Query .hierarchy(document.body, { parent(node: Node) { return node.parentNode; }, children(node: Node) { return node.childNodes; } }); // disable all buttons doc .descendants() .where((node: Node): node is HTMLButtonElement => node.type === "BUTTON") .forEach(node => { node.disabled = true; }); // get all thumbnails let thumbnails = doc .descendants() .filter(node => node.type === "IMG") .map(node => node) .filter(img => img.height < 32 && img.width < 32) .toArray(); ``` ## Supported ECMAScript Editions - [ES2017](#es2017-support-default) (default) - [ES2015](#es2015-support) - [ES5](#es5-support) ### ES2017 Support (default) The **iterable-query** library can be used in an ES2017-compatible runtime by importing `"iterable-query"`: ```ts // TypeScript import { Query } from "iterable-query"; // JavaScript const { Query } = require("iterable-query"); // TypeScript (functional style) import { filter, groupBy } from "iterable-query/fn"; // JavaScript (functional style) const { filter, groupBy } = require("iterable-query/fn"); ``` The default implementation requires a host that supports ES2017 at a minimum. This means support for: - `Symbol` and `Symbol.iterator` - `Promise` - `Map` - `Set` - `WeakMap` - `WeakSet` - `for..of` - Generator Functions - Async Functions The following ES2018 features are polyfilled: - `Symbol.asyncIterator` (via `Symbol.for("Symbol.asyncIterator")`). The following ES2018 features are *not* required to use the default (ES2017) version: - Async Generator Functions (internal use is transpiled) In addition, we also provide downlevel support for [ES2015](#es2015-support) and [ES5](#es5-support). ### ES2015 Support The **iterable-query** library can be used in an ES2015-compatible runtime by importing `"iterable-query/es2015"`: ```ts // TypeScript import { Query } from "iterable-query/es2015"; // JavaScript const { Query } = require("iterable-query/es2015"); // TypeScript (functional style) import { filter, groupBy } from "iterable-query/es2015/fn"; // JavaScript (functional style) const { filter, groupBy } = require("iterable-query/es2015/fn"); ``` The ES2015 implementation requires a host that supports ES2015 at a minimum. This means support for: - `Symbol` and `Symbol.iterator` - `Promise` - `Map` - `Set` - `WeakMap` - `WeakSet` - `for..of` - Generator Functions The following ES2018 features are polyfilled: - `Symbol.asyncIterator` (via `Symbol.for("Symbol.asyncIterator")`). The following ES2017 features are *not* required to use the ES2015 version: - Async Functions (internal use is transpiled) The ES2015 version of the library has all of the same features as the normal version. ### ES5 Support The **iterable-query** library can be used in an ES5-compatible runtime by importing `"iterable-query/es5"`: ```ts // TypeScript import { Query } from "iterable-query/es5"; // JavaScript var iq = require("iterable-query/es5"), Query = iq.Query; // TypeScript (functional style) import { filter, groupBy } from "iterable-query/es2015/fn"; // JavaScript (functional style) var fn = require("iterable-query/es2015/fn"), filter = fn.filter, groupBy = fn.groupBy; ``` The ES5 version of the library has all of the same features as the normal version. The ES5 implementation requires a host that supports ES5 at a minimum. This means support for: - `Object.create` and `Object.defineProperty` The following ES2015 features are *not* polyfilled and require you to supply a runtime polyfill: - `Promise` The following ES2015 features are polyfilled: - `Symbol` and `Symbol.iterator` (which produce strings) - `Map` - `Set` - `WeakMap` - `WeakSet` The following ES2017 features are polyfilled: - `Symbol.asyncIterator` (via `Symbol.for("Symbol.asyncIterator")`). The following ES2015 and ES2017 features are *not* required to use the ES5 version: - `for..of` - Generator Functions (internal use is transpiled) - Async Functions (internal use is transpiled) --- _Source: https://npm.io/package/iterable-query · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._