Question 1

Can I use capture groups in the replacement string?

Accepted Answer

Yes. Use $1, $2, etc. to reference capture groups in the replacement. For example, pattern (\w+)\s(\w+) with replacement $2 $1 swaps the first two words. Named groups can be referenced with $<name> in modern JavaScript regex.

Question 2

How do I replace all occurrences, not just the first?

Accepted Answer

Enable the g (global) flag. Without g, only the first match is replaced. With g, all non-overlapping matches throughout the text are replaced. Using replaceAll() equivalent is what the g flag enables.

Question 3

What special characters need escaping in the pattern?

Accepted Answer

These characters have special meaning and must be escaped with \ when you want to match them literally: . * + ? ^ $ { } [ ] | ( ) \. For example, to match a literal dot, use \. instead of . (which matches any character).

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