Work through the task
Inspect JavaScript regular-expression matches in a bounded worker.
- Choose Test pattern and enter a pattern without slash delimiters, supported flags and source text.
- Read matched text, captures and UTF-16 indices. Generator presets create patterns only; test them against actual examples.
- Review the result before copying or downloading. Editing an input invalidates the previous result; keep an original if the transformation matters.
Example to check
Pattern (?<word>[A-Z][a-z]+), flags g, source Ada and Grace → names at UTF-16 indices 0 and 8.
Limits and output behavior
Pattern/flags are limited to 1,000 UTF-16 units each, source to 100,000, displayed matches to 1,000. Test computation has a 1.5-second budget after startup. The simple-date preset checks shape, not calendar validity.
Troubleshooting
Enter a pattern without slash delimiters and use supported flags. Reduce input or simplify the expression if the bounded worker stops; generator presets only produce a pattern.
Questions
Does a generated date pattern prove that a date exists?
No. The simple-date preset checks shape. Calendar validity and application rules require separate checks.
Input and privacy
Processing runs in this browser. Inputs are not saved automatically. An explicitly chosen local draft, where offered, is plaintext storage on this device. Downloaded files, clipboard contents and browser extensions have separate retention behavior.