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getPath ​

Problem ​

You need to safely read a deeply nested property from an object using a string path — without writing chained optional chaining or try-catch blocks.

Solution ​

Use getPath(item, path, options?) for safe dot-notation access. Bracket notation is auto-converted by default.

ts
import { getPath } from '@vielzeug/arsenal';

const config = { api: { host: 'localhost', port: 3000 }, items: [10, 20] };

getPath(config, 'api.port'); // 3000
getPath(config, 'items[1]'); // 20 — bracket auto-converted
getPath(config, 'api.timeout'); // undefined

Default values ​

ts
import { getPath } from '@vielzeug/arsenal';

getPath(config, 'api.timeout', { fallback: 5_000 }); // 5000
getPath(config, 'missing.deep', { fallback: null }); // null

Strict mode — throw on missing path ​

ts
import { getPath } from '@vielzeug/arsenal';

getPath(config, 'api.missing', { strict: true });
// throws Error: path segment 'missing' not found

Disable bracket auto-conversion ​

ts
import { getPath } from '@vielzeug/arsenal';

getPath(config, 'items[0]', { bracketNotation: false });
// throws TypeError — use 'items.0' instead

Pitfalls ​

  • The option key is fallback, not default or defaultValue.
  • Bracket notation is on by default — pass { bracketNotation: false } to reject it.
  • Unsafe segments (__proto__, constructor, prototype) return options.fallback silently.