Regular Expressions 101

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PCRE2 (PHP >=7.3)
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Positive Lookbehind

(?<=^|;|<\?php\s|<\?\s)

Assert that the Regex below matches

1st Alternative

^ asserts position at start of a line

2nd Alternative

;

; matches the character ; with index 59₁₀ (3B₁₆ or 73₈) literally (case insensitive)

3rd Alternative

<\?php\s

< matches the character < with index 60₁₀ (3C₁₆ or 74₈) literally (case insensitive)

\? matches the character ? with index 63₁₀ (3F₁₆ or 77₈) literally (case insensitive)

php

matches the characters php literally (case insensitive)

\s matches any whitespace character (equivalent to [\r\n\t\f\v ])

4th Alternative

<\?\s

< matches the character < with index 60₁₀ (3C₁₆ or 74₈) literally (case insensitive)

\? matches the character ? with index 63₁₀ (3F₁₆ or 77₈) literally (case insensitive)

\s matches any whitespace character (equivalent to [\r\n\t\f\v ])

1st Capturing Group

(\s*?)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)

2nd Capturing Group

(\h*define\s*\(\s*[\'"](\w*?)[\'"]\s*)

matches any horizontal whitespace character (equivalent to [[:blank:]])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

define

matches the characters define literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

\( matches the character ( with index 40₁₀ (28₁₆ or 50₈) literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

Match a single character present in the list below

[\'"]

\' matches the character ' with index 39₁₀ (27₁₆ or 47₈) literally (case insensitive)

" matches the character " with index 34₁₀ (22₁₆ or 42₈) literally (case insensitive)

3rd Capturing Group

(\w*?)

matches any word character (equivalent to [a-zA-Z0-9_])

*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)

Match a single character present in the list below

[\'"]

\' matches the character ' with index 39₁₀ (27₁₆ or 47₈) literally (case insensitive)

" matches the character " with index 34₁₀ (22₁₆ or 42₈) literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

4th Capturing Group

(,\s*([\'"].*?[\'"]|.*?)\s*)

, matches the character , with index 44₁₀ (2C₁₆ or 54₈) literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

5th Capturing Group

([\'"].*?[\'"]|.*?)

1st Alternative

[\'"].*?[\'"]

Match a single character present in the list below

[\'"]

\' matches the character ' with index 39₁₀ (27₁₆ or 47₈) literally (case insensitive)

" matches the character " with index 34₁₀ (22₁₆ or 42₈) literally (case insensitive)

matches any character

*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)

Match a single character present in the list below

[\'"]

\' matches the character ' with index 39₁₀ (27₁₆ or 47₈) literally (case insensitive)

" matches the character " with index 34₁₀ (22₁₆ or 42₈) literally (case insensitive)

2nd Alternative

.*?

matches any character

*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

6th Capturing Group

((?:,\s*(?:true|false)\s*)?\)\s*;)

Non-capturing group

(?:,\s*(?:true|false)\s*)?

? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)

, matches the character , with index 44₁₀ (2C₁₆ or 54₈) literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

Non-capturing group

(?:true|false)

1st Alternative

true

matches the characters true literally (case insensitive)

2nd Alternative

false

matches the characters false literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

\) matches the character ) with index 41₁₀ (29₁₆ or 51₈) literally (case insensitive)

matches any whitespace character (equivalent to [\r\n\t\f\v ])

* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)

; matches the character ; with index 59₁₀ (3B₁₆ or 73₈) literally (case insensitive)

Global pattern flags

i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])

m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)

s modifier: single line. Dot matches newline characters

g modifier: global. All matches (don't return after first match)

Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expressions 101

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Regular Expressions 101

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Regular Expressions 101

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