Regular Expressions 101

^start of line

Character Class[A-Z]

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

Negative Lookahead(?![^\d\n]*(\d)(?:[^\d\n]*\1)+[^\d\n]*$)

Negated Character Class[^\d\n]*

*matches any number of characters outside the set below:

\da digit

\na line-feed (newline) character (ASCII 10)

Group 1(\d)

\da digit

Non-Capturing Group(?:[^\d\n]*\1)+

+repeats the group contents below at least once:

Negated Character Class[^\d\n]*

*matches any number of characters outside the set below:

\da digit

\na line-feed (newline) character (ASCII 10)

\1the text saved by group 1

Negated Character Class[^\d\n]*

*matches any number of characters outside the set below:

\da digit

\na line-feed (newline) character (ASCII 10)

$end of line

Positive Lookahead(?=.{2,15}$)

.{2,15}any character (except for line terminators), repeated between 2 and 15 times

$end of line

Character Class[A-Z0-9]*

*matches any number of characters from the set below:

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

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

Non-Capturing Group(?:-[A-Z0-9]*){0,2}

{0,2}repeats the group contents below between 0 and 2 times:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[A-Z0-9]*

*matches any number of characters from the set below:

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

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

Character Class[A-Z0-9]+

+matches at least one character from the set below:

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

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

$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

No unit tests · Add a test to get started

27 tokens

Regular Expression

^[A-Z](?![^\d\n]*(\d)(?:[^\d\n]*\1)+[^\d\n]*$)(?=.{2,15}$)[A-Z0-9]*(?:-[A-Z0-9]*){0,2}[A-Z0-9]+$

Unit Tests

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