Regular Expressions 101

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  • PCRE2 (PHP >=7.3)
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  • ECMAScript (JavaScript)
  • Python 2.7
  • Golang (RE2)


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Non-capturing group
1st Alternative
\G asserts position at the end of the previous match or the start of the string for the first match
Negative Lookahead
Assert that the Regex below does not match
\A asserts position at start of the string
2nd Alternative
'prices'=> matches the characters 'prices'=> literally (case sensitive)
\[ matches the character [ literally (case sensitive)
Match a single character present in the list below
* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\d matches a digit zero through nine in any script except ideographic scripts (equal to \p{Nd})
. matches the character . literally (case sensitive)
\K resets the starting point of the reported match. Any previously consumed characters are no longer included in the final match
matches any horizontal whitespace character (equal to [[:blank:]])
+ Quantifier — Matches between one and unlimited times, as many times as possible, giving back as needed (greedy)
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)
u modifier: unicode. Pattern strings are treated as UTF-16. Also causes escape sequences to match unicode characters
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match


Test String