Regular Expressions 101

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  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
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  • Match
  • Substitution
  • List
  • Unit Tests (17)

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An explanation of your regex will be automatically generated as you type.

Regular Expression

Regex Versions

/

Delimiters

/
i

Regex Flags

Unit Tests

given the string +2 assert that regex does match
given the string abc assert that regex does not match
given the string 0.3e0 assert that regex does match
given the string 0.3e+10 assert that regex does match
given the string 0.3e-10 assert that regex does match
given the string 0.3e10 assert that regex does match
given the string -3e-2 assert that regex does match
given the string 3e2 assert that regex does match
given the string -.3 assert that regex does match
given the string 3. assert that regex does match
given the string .3e2 assert that regex does match
given the string -3e0 assert that regex does match
given the string 3e10 assert that regex does match
given the string -2.3 assert that regex does match
given the string -2 assert that regex does match
given the string 2.5 assert that regex does match
given the string 2 assert that regex does match

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