Regular Expressions 101

^start of line

Character Class[v]

vthe literal v (118₁₀ / 166₈ / 76₁₆) (case sensitive)

Group 1((\d?\d\.)(0\.|[1-9]?[0-9]\.)([1-9]?[0-9]|))

Group 2(\d?\d\.)

\d?optionally matches a digit

\da digit

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 3(0\.|[1-9]?[0-9]\.)

1st Alternative0\.

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

2nd Alternative[1-9]?[0-9]\.

Character Class[1-9]?

?matches at most one character from the set below:

1-9one character from 1 (49₁₀) to 9 (57₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Group 4([1-9]?[0-9]|)

1st Alternative[1-9]?[0-9]

Character Class[1-9]?

?matches at most one character from the set below:

1-9one character from 1 (49₁₀) to 9 (57₁₀)

Character Class[0-9]

0-9one character from 0 (48₁₀) to 9 (57₁₀)

2nd Alternative — matches an empty string

$end of line

Global pattern flags

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

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^[v]((\d?\d\.)(0\.|[1-9]?[0-9]\.)([1-9]?[0-9]|))$

New

v0.1.2
v12.1.0
v0.0.1
v0.12.0
v10.10.10
10.10.10
v222.10.0
v0.999.0
v0.1.111
v0.01.0
v0.1.01
v12.1
v12