Regular Expressions 101

Explanation

Pro

^start of line

Non-Capturing Group(?:\\\\)*

*repeats the group contents below any number of times:

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

:hellothe literal text :hello (case sensitive)

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

Match Information

Detailed match information will be displayed here automatically.

Quick Reference

25 tokens

Regular Expression

^(?:\\\\)*:hello

New

:hello test will match :hello
\:hello test will not match
\\:hello test will match :hello
\\\:hello test will not match
\\\\:hello test will match :hello
\\\\\:hello test will not match
\\\\\\:hello test will match :hello

Substitution

:hello test will match :hello
\:hello test will not match
\\:hello test will match :hello
\\\:hello test will not match
\\\\:hello test will match :hello
\\\\\:hello test will not match
\\\\\\:hello test will match :hello