Question 1

What is a regular expression?

Accepted Answer

A regular expression (regex) is a sequence of characters that defines a search pattern. It's used for pattern matching, text search, and text manipulation in programming.

Question 2

What do the regex flags mean?

Accepted Answer

g (global) finds all matches, i (case-insensitive) ignores case, m (multiline) treats ^ and $ as line boundaries, s (dotAll) makes . match newlines, u (unicode) enables unicode support.

Question 3

How do I escape special characters?

Accepted Answer

Special characters like . * + ? ^ $ { } [ ] \ | ( ) need to be escaped with a backslash. For example, to match a literal dot, use \. instead of just a dot.

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