Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = '<!--- petofma 20090716: new CED LDAP server now wants applications to authenticate! ---> <CFLDAP server="#session.comldapserver#" port="#session.comldapport#" action="QUERY" name="results" start="ou=People, o=#session.comldaproot#" username="#server.comLdapLogin#" password="#server.comLdapPass#" scope="onelevel" filter="(&#filterstring#(recordStatus=a)#Iif(IsDefined("dgfish_only"),DE("(sourceOrganisation=COM)(dg=MARE)"),DE(""))#)" sort="uid" attributes="dn,employeeNumber,ecSYSPERNumber,gestelNumber,uid,title,cn,dg,departmentNumber,telephoneNumber,facsimilenumber,l,mail,physicalDeliveryOfficeName,sourceOrganisation,employeeType,contractExpiryDate,recordStatus,modifytimestamp,source,manager"> <CFOUTPUT> <P>Found <b>#results.RecordCount# User#Iif(results.RecordCount EQ 1,DE(""),DE("s"))#</b> matching your search criteria: </CFOUTPUT> <cfif IsDebugMode()> <cfdump var=#results#> </cfif> '; my $regex = qr/(<cfldap[^>]* name ?= ?")(.*?)("[^>]*)( sort ?= ?"(.*?)")(.*?>)/ip; my $subst = '$1unsortedResults$3$6\\n<cfquery dbtype="query" name="$2">SELECT * FROM unsortedResults ORDER BY $5</cfquery>\\n'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html