Regular Expressions 101

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  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8


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  • Substitution
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  • Unit Tests
\[ matches the character [ with index 9110 (5B16 or 1338) literally (case sensitive)
Match a single character present in the list below
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\S matches any non-whitespace character (equivalent to [^\r\n\t\f\v ])
\] matches the character ] with index 9310 (5D16 or 1358) literally (case sensitive)
Global pattern flags
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 Expression
No Match


Test String