Regular Expressions 101

(?i)applies the following effective flags to the remainder of the pattern: gi

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

Negative Lookbehind(?<!\b[01][0-9])

\ba Unicode word boundary

Character Class[01]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[0-9]

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

Negative Lookbehind(?<!\b[2][0-3])

\ba Unicode word boundary

Character Class[2]

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-3]

0-3one character from 0 (48₁₀) to 3 (51₁₀)

Group 1([^\S\r\n]*:)

Negated Character Class[^\S\r\n]*

*matches any number of characters outside the set below:

\Sany character that is not Unicode whitespace

\ra carriage return (ASCII 13)

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

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Negated Character Class[^\S\r\n]*

*matches any number of characters outside the set below:

\Sany character that is not Unicode whitespace

\ra carriage return (ASCII 13)

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

Negative Lookahead(?![0-5][0-9](?:[ap]\.?m\b\.?)?)

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

Character Class[0-9]

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

Non-Capturing Group(?:[ap]\.?m\b\.?)?

?repeats the group contents below at most once:

Character Class[ap]

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

pthe literal p (112₁₀ / 160₈ / 70₁₆) (case insensitive)

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

mthe literal m (109₁₀ / 155₈ / 6D₁₆) (case insensitive)

\ba Unicode word boundary

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

Global pattern flags

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?i)(?<!\b[01][0-9])(?<!\b[2][0-3])([^\S\r\n]*:)[^\S\r\n]*(?![0-5][0-9](?:[ap]\.?m\b\.?)?)

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Regular Expression

Extraction