Regular Expressions 101

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  • PCRE2 (PHP >=7.3)
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1st Alternative
! matches the character ! with index 3310 (2116 or 418) literally (case sensitive)
2nd Alternative
Match a single character not present in the list below
? matches the character ? with index 6310 (3F16 or 778) literally (case sensitive)
P matches the character P with index 8010 (5016 or 1208) literally (case sensitive)
1st Capturing Group
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
1st Alternative
matches the characters CG literally (case sensitive)
2nd Alternative
G matches the character G with index 7110 (4716 or 1078) literally (case sensitive)
. matches any character (except for line terminators)
. matches any character (except for line terminators)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match


Test String