regexparam

import { parse, inject } from 'regexparam'; // A helper function to extract parameters from a matched path function exec(path: string, result: ReturnType<typeof parse>): Record<string, string | null> { let i = 0; const out: Record<string, string | null> = {}; const matches = result.pattern.exec(path); if (!matches) { return {}; // No match } while (i < result.keys.length) { // Matches array index starts from 1 for captured groups out[result.keys[i]] = matches[++i] || null; } return out; } // Example 1: Parsing a route with optional parameters const route1 = parse('/books/:genre/:title?'); console.log('Route 1 pattern:', route1.pattern.source); console.log('Route 1 keys:', route1.keys); const path1a = '/books/horror'; console.log(`Matching "${path1a}":`, route1.pattern.test(path1a)); console.log(`Extracted params for "${path1a}":`, exec(path1a, route1)); const path1b = '/books/science-fiction/dune'; console.log(`Matching "${path1b}":`, route1.pattern.test(path1b)); console.log(`Extracted params for "${path1b}":`, exec(path1b, route1)); // Example 2: Injecting parameters into a route const injectedPath1 = inject('/users/:id', { id: 'alice' }); console.log('Injected path (user alice):', injectedPath1); const injectedPath2 = inject('/posts/:slug/*', { slug: 'my-post', '*': 'comments/123' }); console.log('Injected path (post with wildcard):', injectedPath2); // Example 3: Handling missing non-optional parameters during injection const incompleteInjection = inject('/products/:category/:item', { category: 'electronics' }); console.log('Incomplete injection:', incompleteInjection); // Missing 'item' parameter