Regular Expressions 101

Pro

Non-Capturing Group(?:\d+|\G(?!^)\d+)

1st Alternative\d+

\d+a digit, repeated at least once

2nd Alternative\G(?!^)\d+

\Gstart of current search

Negative Lookahead(?!^)

^start of line

\d+a digit, repeated at least once

\Kresets the starting point of the reported match. Any previously consumed characters are no longer included in the final match

Character Class[- ]+

+matches at least one character from the set below:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

the literal (32₁₀ / 40₈ / 20₁₆)

Positive Lookahead(?=\d)

\da digit

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

(?:\d+|\G(?!^)\d+)\K[- ]+(?=\d)

New

1234567890
12-34 567 890
   12-34 567 890---
- - 12-34 567 890- - - 
-   -12----34    56    7 8   9   0- - - 
 09 777 55 888

1234567890
12-34 567 890
   12-34 567 890---
- - 12-34 567 890- - - 
-   -12----34    56    7 8   9   0- - - 
 09 777 55 888