Regular Expressions 101

Explanation

Pro

Non-Capturing Group(?:[^%\d]|^|\b(?=%))

1st Alternative[^%\d]

Negated Character Class[^%\d]

%the literal % (37₁₀ / 45₈ / 25₁₆)

\da digit

2nd Alternative^

^start of string

3rd Alternative\b(?=%)

\ban ASCII word boundary

Positive Lookahead(?=%)

%the literal % (37₁₀ / 45₈ / 25₁₆)

Non-Capturing Group(?:%%)*

*repeats the group contents below any number of times:

%%the literal text %%

Group 1(\d+)

\d+a digit, repeated at least once

Global pattern flags

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

Detailed match information will be displayed here automatically.

26 tokens

(?:[^%\d]|^|\b(?=%))(?:%%)*(\d+)

New

abcd %1 %%2 %%%3 %%%%4 efgh

abcd%12%%34%%%666%%%%11efgh
%%6%%7%%8
123
abc123