regex101: JavaScript Match Workspace

1st Alternative(?<=ALPHA|[Aa]lpha|ALPHA[-\.]|[Aa]lpha[-\.])[0-9]+

Positive Lookbehind(?<=ALPHA|[Aa]lpha|ALPHA[-\.]|[Aa]lpha[-\.])

1st AlternativeALPHA

ALPHAthe literal text ALPHA (case sensitive)

2nd Alternative[Aa]lpha

Character Class[Aa]

Athe literal A (65₁₀ / 101₈ / 41₁₆) (case sensitive)

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

lphathe literal text lpha (case sensitive)

3rd AlternativeALPHA[-\.]

ALPHAthe literal text ALPHA (case sensitive)

Character Class[-\.]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

4th Alternative[Aa]lpha[-\.]

Character Class[Aa]

Athe literal A (65₁₀ / 101₈ / 41₁₆) (case sensitive)

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

lphathe literal text lpha (case sensitive)

Character Class[-\.]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

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

2nd Alternative(?<=BETA|[Bb]eta|BETA[-\.]|[Bb]eta[-\.])[0-9]+

Positive Lookbehind(?<=BETA|[Bb]eta|BETA[-\.]|[Bb]eta[-\.])

1st AlternativeBETA

BETAthe literal text BETA (case sensitive)

2nd Alternative[Bb]eta

Character Class[Bb]

Bthe literal B (66₁₀ / 102₈ / 42₁₆) (case sensitive)

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

etathe literal text eta (case sensitive)

3rd AlternativeBETA[-\.]

BETAthe literal text BETA (case sensitive)

Character Class[-\.]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

4th Alternative[Bb]eta[-\.]

Character Class[Bb]

Bthe literal B (66₁₀ / 102₈ / 42₁₆) (case sensitive)

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

etathe literal text eta (case sensitive)

Character Class[-\.]

-the literal - (45₁₀ / 55₈ / 2D₁₆)

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

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

3rd Alternative(?<=RC|[Rr]c|RC[-\.]|[Rc]c[-\.])[0-9]+

Positive Lookbehind(?<=RC|[Rr]c|RC[-\.]|[Rc]c[-\.])

1st AlternativeRC

RCthe literal text RC (case sensitive)

2nd Alternative[Rr]c

3rd AlternativeRC[-\.]

4th Alternative[Rc]c[-\.]

Character Class[0-9]+

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

26 tokens

Regular Expression

(?<=ALPHA|[Aa]lpha|ALPHA[-\.]|[Aa]lpha[-\.])[0-9]+|(?<=BETA|[Bb]eta|BETA[-\.]|[Bb]eta[-\.])[0-9]+|(?<=RC|[Rr]c|RC[-\.]|[Rc]c[-\.])[0-9]+

New

// Correct prerelease versions
TESTNG7-BETA-8-SNAPSHOT
rc1
TESTNG6-Alpha1
RC.3

// Incorrect prerelease versions
BETA-SNAPSHOT-7
B.1
RC/1
AlPhA-1
bETA-2

Substitution

// Correct prerelease versions
TESTNG7-BETA-8-SNAPSHOT
rc1
TESTNG6-Alpha1
RC.3

// Incorrect prerelease versions
BETA-SNAPSHOT-7
B.1
RC/1
AlPhA-1
bETA-2