Regular Expressions 101

Pro

^start of line

Group 1(\d+)

\d+a digit, repeated at least once

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

1st Alternative\.+

\.+the literal . (46₁₀ / 56₈ / 2E₁₆) , repeated at least once

2nd Alternative(\.)\.*(\d)\.*(\d).*

Group 2(\.)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\.*the literal . (46₁₀ / 56₈ / 2E₁₆) , repeated any number of times

Group 3(\d)

\da digit

\.*the literal . (46₁₀ / 56₈ / 2E₁₆) , repeated any number of times

Group 4(\d)

\da digit

.*any character (except for line terminators), repeated any number of times

$end of line

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+)(?:\.+|(\.)\.*(\d)\.*(\d).*)$

New

123.12
12
12.13
12.
12.555
12....
12.
12.35.12.14
12..2..5

$1$2$3$4

123.12
12
12.13
12.
12.555
12....
12.
12.35.12.14
12..2..5