Level 112 Level 114
Level 113

RegEx: Parentheses


4 words 0 ignored

Ready to learn       Ready to review

Ignore words

Check the boxes below to ignore/unignore words, then click save at the bottom. Ignored words will never appear in any learning session.

All None

Ignore?
R(?#comment)
Matches "R". All the rest is a comment
R(?i)uby
Case-insensitive while matching "uby"
R(?i:uby)
Same as above
rub(?:y|le))
Group only without creating \1 backreference