{"id":12266,"library":"u3","title":"u3 Utility Functions","description":"The package `u3` (version 0.1.1) provides a small collection of general-purpose utility functions, primarily demonstrated with `cache` for function memoization and `eachCombination` for iterating through all permutations of given alternatives. First released in 2016, its low version number and lack of recent updates strongly suggest it is no longer actively maintained, making it an abandoned project. Its primary differentiators are its minimal footprint and specific focus on these two common patterns, likely intended for internal project use rather than a broad utility library like Lodash or Underscore. It exclusively uses CommonJS modules, reflecting its age, and does not appear to have a defined release cadence beyond its initial publication. It was designed to offer basic helper functions for related projects such as `e3` and `dataflower`.","status":"abandoned","version":"0.1.1","language":"javascript","source_language":"en","source_url":"https://github.com/inf3rno/u3","tags":["javascript","utility functions"],"install":[{"cmd":"npm install u3","lang":"bash","label":"npm"},{"cmd":"yarn add u3","lang":"bash","label":"yarn"},{"cmd":"pnpm add u3","lang":"bash","label":"pnpm"}],"dependencies":[],"imports":[{"note":"This package is CommonJS-only and does not support ES module `import` syntax.","wrong":"import u3 from 'u3';","symbol":"u3","correct":"const u3 = require('u3');"},{"note":"The `cache` function is a named export available through CommonJS destructuring. Direct ES module imports are not supported.","wrong":"import { cache } from 'u3';","symbol":"cache","correct":"const { cache } = require('u3');"},{"note":"The `eachCombination` function is a named export available through CommonJS destructuring. Direct ES module imports are not supported.","wrong":"import { eachCombination } from 'u3';","symbol":"eachCombination","correct":"const { eachCombination } = require('u3');"}],"quickstart":{"code":"const u3 = require('u3');\n\n// Use the cache function for memoization\nconst memoizedSum = u3.cache(function calculateSum(x, y, z) {\n    console.log('Calculating sum for:', x, y, z);\n    return x + y + z;\n});\n\nconsole.log('Memoized sum (first call):', memoizedSum(1, 2, 3)); // Output: Calculating sum for: 1 2 3, Memoized sum (first call): 6\nconsole.log('Memoized sum (subsequent call, arguments ignored):', memoizedSum(10, 20, 30)); // Output: Memoized sum (subsequent call, arguments ignored): 6\n\n// Cache a simple value directly\nconst cachedValue = u3.cache(Math.PI * 2);\nconsole.log('Cached value:', cachedValue()); // Output: Cached value: 6.283185307179586\n\n// Use eachCombination to iterate through permutations\nconsole.log('\\n--- Combinations ---');\nu3.eachCombination([\n    [10, 20, 30],\n    ['A', 'B']\n], function() {\n    console.log.apply(console, arguments);\n});\n/* Expected console output for combinations:\n10, A\n10, B\n20, A\n20, B\n30, A\n30, B\n*/","lang":"javascript","description":"Demonstrates how to import `u3` using CommonJS `require`, utilize the `cache` function for memoizing both function results and raw values, and iterate through combinations using `eachCombination`."},"warnings":[{"fix":"Use `const u3 = require('u3');` for imports. If using in an ES module environment, consider a CJS-to-ESM wrapper or transpilation.","message":"This package is strictly CommonJS-only. Attempting to use ES module `import` statements will result in a runtime error in Node.js environments unless configured for ESM compatibility.","severity":"breaking","affected_versions":">=0.1.1"},{"fix":"Be aware that `cache` does not implement argument-based memoization (like a true `memoize` function). If you need caching specific to argument sets, you'll need a different utility or a custom implementation.","message":"The `cache` function provided only memoizes the *first* result of the function it wraps, or the initial value provided. Subsequent calls, even with different arguments, will return the original cached value without re-execution.","severity":"gotcha","affected_versions":">=0.1.1"},{"fix":"For new projects, consider using actively maintained and more robust utility libraries (e.g., Lodash, Underscore.js) or modern native JavaScript features for similar functionalities like memoization (e.g., using `Map` for simple caching) and array iteration.","message":"The `u3` package appears to be abandoned, with its last known activity and release dating back to 2016. There are no active maintainers, and it is highly unlikely to receive updates, bug fixes, or security patches.","severity":"deprecated","affected_versions":">=0.1.1"}],"env_vars":null,"last_verified":"2026-04-19T00:00:00.000Z","next_check":"2026-07-18T00:00:00.000Z","problems":[{"fix":"Change your import statement from `import { someFunction } from 'u3';` to `const { someFunction } = require('u3');`. Ensure your `package.json` does not specify `\"type\": \"module\"` if you intend to run as CommonJS.","cause":"Attempting to use `import` syntax (ES modules) in a project that is configured for CommonJS, or for a CommonJS-only package.","error":"SyntaxError: Cannot use import statement outside a module"},{"fix":"Verify that `const u3 = require('u3');` is correctly placed and that you are accessing the functions as properties of the `u3` object (e.g., `u3.cache(...)`) or correctly destructuring `const { cache, eachCombination } = require('u3');`.","cause":"This error typically occurs when trying to call `u3.cache` or `u3.eachCombination` after `u3` has been imported incorrectly, or if the property is undefined.","error":"TypeError: u3.cache is not a function"}],"ecosystem":"npm"}