{"id":14501,"library":"collection-utils","title":"Collection Utilities","description":"The `collection-utils` package, at version `1.0.1`, provides a set of fundamental utility functions designed to simplify common operations on JavaScript collections, primarily arrays and objects. Published by `quicktype`, a project focused on generating type bindings from JSON schemas, this library likely serves as an internal dependency or a lightweight, standalone offering for basic collection manipulation. It ships with TypeScript types, facilitating type-safe usage in TypeScript projects. Given its current version, it appears stable but may have a focused, rather than expansive, feature set, with a release cadence potentially tied to the `quicktype` ecosystem's needs. Key differentiators, beyond its small footprint and TypeScript support, are not explicitly detailed in public documentation, suggesting a design for efficiency and straightforward use rather than broad, complex functionality found in larger utility libraries like Lodash.","status":"active","version":"1.0.1","language":"javascript","source_language":"en","source_url":"https://github.com/quicktype/collection-utils","tags":["javascript","typescript"],"install":[{"cmd":"npm install collection-utils","lang":"bash","label":"npm"},{"cmd":"yarn add collection-utils","lang":"bash","label":"yarn"},{"cmd":"pnpm add collection-utils","lang":"bash","label":"pnpm"}],"dependencies":[],"imports":[{"note":"This library is primarily designed for ES modules. While CommonJS might technically work, ESM named imports are the canonical and recommended approach for tree-shaking and modern tooling.","wrong":"const map = require('collection-utils').map;","symbol":"map","correct":"import { map } from 'collection-utils';"},{"note":"Functions are exported individually as named exports, promoting modularity and efficient bundling. Avoid attempting to import a default object containing all utilities.","wrong":"import collectionUtils from 'collection-utils'; collectionUtils.filter(...);","symbol":"filter","correct":"import { filter } from 'collection-utils';"},{"note":"Common utility functions like `isEmpty` are provided as direct named exports. Ensure your tooling is configured for ES module resolution.","symbol":"isEmpty","correct":"import { isEmpty } from 'collection-utils';"}],"quickstart":{"code":"import { map, filter, isEmpty } from 'collection-utils';\n\ninterface User { id: number; name: string; isActive: boolean; roles: string[]; }\n\nconst users: User[] = [\n  { id: 1, name: 'Alice', isActive: true, roles: ['admin', 'editor'] },\n  { id: 2, name: 'Bob', isActive: false, roles: ['viewer'] },\n  { id: 3, name: 'Charlie', isActive: true, roles: ['editor'] },\n  { id: 4, name: 'David', isActive: false, roles: [] }\n];\n\n// Use 'map' to transform a collection\nconst userNames = map(users, user => user.name);\nconsole.log('User Names:', userNames); // Expected: ['Alice', 'Bob', 'Charlie', 'David']\n\n// Use 'filter' to select elements based on a condition\nconst activeEditors = filter(users, user => user.isActive && user.roles.includes('editor'));\nconsole.log('Active Editors:', activeEditors.map(u => u.name)); // Expected: ['Alice', 'Charlie']\n\n// Use 'isEmpty' to check if a collection is empty\nconst hasActiveUsers = !isEmpty(filter(users, user => user.isActive));\nconsole.log('Are there any active users?', hasActiveUsers); // Expected: true\n\nconst emptyArray: any[] = [];\nconsole.log('Is emptyArray empty?', isEmpty(emptyArray)); // Expected: true\n\nconst emptyObject = {};\nconsole.log('Is emptyObject empty?', isEmpty(emptyObject)); // Expected: true\n","lang":"typescript","description":"Demonstrates basic usage of `map`, `filter`, and `isEmpty` functions on both arrays and objects, showcasing type-safe operations."},"warnings":[{"fix":"Always assume potential mutation unless documentation states otherwise. For critical state, explicitly create deep copies of objects/arrays before passing them to utility functions using `structuredClone` or a dedicated deep-cloning utility.","message":"Many collection utility functions, especially those interacting with objects, might operate on shallow copies or mutate inputs if not explicitly designed for immutability. Always check function documentation or test for mutation if immutability is critical.","severity":"gotcha","affected_versions":">=1.0.0"},{"fix":"For performance-critical sections with very large datasets, consider direct `for...of` or `for` loops, or specialized data structures. For most common use cases, the overhead is negligible.","message":"Performance considerations: While convenient, using utility functions on extremely large collections (thousands or millions of items) in tight loops can introduce overhead compared to raw JavaScript loops. Profile your code if performance becomes a bottleneck.","severity":"gotcha","affected_versions":">=1.0.0"},{"fix":"Review the source code or specific API documentation for available functions. If a required utility is missing, consider importing it from another specialized library or implementing it manually.","message":"The library is relatively minimal. Developers coming from larger utility libraries like Lodash or Ramda might expect a broader array of specialized functions (e.g., deep merge, debounce, throttle, advanced string manipulation) which are not present here.","severity":"gotcha","affected_versions":">=1.0.0"}],"env_vars":null,"last_verified":"2026-04-19T00:00:00.000Z","next_check":"2026-07-18T00:00:00.000Z","problems":[{"fix":"Ensure you are using named imports: `import { map } from 'collection-utils';`. Verify your bundler (e.g., Webpack, Rollup) is configured for ES module resolution and tree-shaking correctly, especially in environments where CommonJS is prevalent.","cause":"This typically indicates that the module was imported incorrectly, or that tree-shaking removed the function because it appeared unused, or a bundler issue.","error":"TypeError: (0 , collection_utils__WEBPACK_IMPORTED_MODULE_0__.map) is not a function"},{"fix":"Use named imports for individual functions: `import { map } from 'collection-utils';`. The library uses named exports for its utilities.","cause":"This TypeScript error means that the imported `collection-utils` module, when treated as a single object (e.g., `import * as utils from 'collection-utils'; utils.map(...)`), does not expose `map` as a property directly on that root object.","error":"Property 'map' does not exist on type 'typeof import(\"collection-utils\")'."}],"ecosystem":"npm"}