regex101: PCRE (Legacy) Match Workspace

Group release(?P<release>(?:0|[1-9])\d*(?:\.(?:0|[1-9]\d*)){2})

Non-Capturing Group(?:0|[1-9])

1st Alternative0

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2nd Alternative[1-9]

Character Class[1-9]

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

\d*a digit, repeated any number of times

Non-Capturing Group(?:\.(?:0|[1-9]\d*)){2}

{2}repeats the group contents below exactly 2 times:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Non-Capturing Group(?:0|[1-9]\d*)

1st Alternative0

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2nd Alternative[1-9]\d*

Character Class[1-9]

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

\d*a digit, repeated any number of times

Non-Capturing Group(?:-(?P<pre>(?P<prel>a|b|rc)(?P<pren>(?:0|[1-9])\d*)))?

?repeats the group contents below at most once:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group pre(?P<pre>(?P<prel>a|b|rc)(?P<pren>(?:0|[1-9])\d*))

Group prel(?P<prel>a|b|rc)

1st Alternativea

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

2nd Alternativeb

bthe literal b (98₁₀ / 142₈ / 62₁₆) (case sensitive)

3rd Alternativerc

rcthe literal text rc (case sensitive)

Group pren(?P<pren>(?:0|[1-9])\d*)

Non-Capturing Group(?:0|[1-9])

1st Alternative0

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

2nd Alternative[1-9]

Character Class[1-9]

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

\d*a digit, repeated any number of times

Non-Capturing Group(?:\+(?P<local>[a-z\d]+(?:[-_\.][a-z\d]+)*))?

?repeats the group contents below at most once:

\+the literal + (43₁₀ / 53₈ / 2B₁₆)

Group local(?P<local>[a-z\d]+(?:[-_\.][a-z\d]+)*)

Character Class[a-z\d]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

\da digit

Non-Capturing Group(?:[-_\.][a-z\d]+)*

*repeats the group contents below any number of times:

Character Class[-_\.]

Character Class[a-z\d]+

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

Search reference

Regular Expression

(?P<release>(?:0|[1-9])\d*(?:\.(?:0|[1-9]\d*)){2})(?:-(?P<pre>(?P<prel>a|b|rc)(?P<pren>(?:0|[1-9])\d*)))?(?:\+(?P<local>[a-z\d]+(?:[-_\.][a-z\d]+)*))?

Test String
New

Valid PEP440 Verions

Final versions
0.9
0.9.1
0.9.2
0.9.10
0.9.11
1.0.1
2.0.1

Version epochs
1.0
1.1
2.0
2013.10
2014.04
2013.10
2014.04
1!1.0
1!1.1
1!2.0

Examples of compliant version schemes
Simple "major.minor" versioning:
0.1
0.2
0.3
1.0
1.1
Simple "major.minor.micro" versioning:
1.1.0
1.1.1
1.1.2
1.2.0
"major.minor" versioning with alpha, beta and candidate pre-releases:
0.9
1.0-a1
1.0-a2
1.0.7-b1
1.0.34-rc1
1.0
1.1.0-a1
"major.minor" versioning with developmental releases, release candidates and post-releases for minor corrections:
0.9
1.0.dev1
1.0.dev2
1.0.dev3
1.0.dev4
1.0c1
1.0c2
1.0
1.0.post1
1.1.dev1
Date based releases, using an incrementing serial within each year, skipping zero:
2012.1
2012.2
2012.3
2012.15
2013.1
2013.2
The following example covers many of the possible combinations:
1.0.dev456
1.0a1
1.0a2.dev456
1.0a12.dev456
1.0a12
1.0b1.dev456
1.0b2
1.0b2.post345.dev456
1.0b2.post345
1.0rc1.dev456
1.0rc1
1.0
1.0+abc.5
1.0+abc.7
1.0+5
1.0.post456.dev34
1.0.post456
1.1.dev1

Regular Expressions 101

Regular Expression

Test String
New

Extraction
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Regular Expression

Test StringNew

ExtractionProcessing...

Test String
New

Extraction
Processing...