Regular Expressions 101

Pro

\Bnot an ASCII word boundary

@the literal @ (64₁₀ / 100₈ / 40₁₆)

Group username(?<username>\w+(?:\.\w+)*)

\w+any word character, repeated at least once

Non-Capturing Group(?:\.\w+)*

*repeats the group contents below any number of times:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\w+any word character, repeated at least once

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

\B@(?<username>\w+(?:\.\w+)*)

New

@men.tion, @men.tion, @men.tion., (@men.tion), and (@men.tion.) should all return men.tion

@men.tion, @men.tion, @men.tion., (@men.tion), and (@men.tion.) should all return men.tion