lodash.identity

import identity from 'lodash.identity'; // Basic usage: identity returns its input directly console.log('Direct usage:', identity(42)); // Expected: 42 console.log('With string:', identity('hello')); // Expected: 'hello' // Useful as a default iterator, e.g., with Array.prototype.map const numbers = [1, 2, 3]; const mappedNumbers = numbers.map(identity); console.log('Mapped numbers (identity):', mappedNumbers); // Expected: [1, 2, 3] // Or with a custom function that expects an iterator function processItems(items, iterator = identity) { return items.map(item => iterator(item)); } const processed = processItems(['a', 'b', 'c']); console.log('Processed with default identity:', processed); // Expected: ['a', 'b', 'c'] const processedWithTransform = processItems(['x', 'y', 'z'], item => item.toUpperCase()); console.log('Processed with transform:', processedWithTransform); // Expected: ['X', 'Y', 'Z'] // In some scenarios, it simplifies code where an explicit no-op is clearer const config = { onComplete: identity // No-op on completion }; console.log('Config onComplete:', config.onComplete('task completed')); // Expected: 'task completed'