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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'Sql.Database("GOULBDB42", "PALMSDB", [Query="SELECT ""tblPOEOLicence"".""InstrumentID"" as LicNo#(lf), ""tblClassification"".""Description"" as Status#(lf), ""tblPOEOLicence"".""AnniversaryDate"" as Anniv_date#(lf), ""tblLocation"".""LocationName"" as Location#(lf), ""tblLGA"".""Name"" as LicLGA#(lf), ""viewInstrumentAccountableParty"".""APName"" as Licensee#(lf), ""tblActivityGroup"".""Description"" as Schudeled_Activity#(lf), ""tblFeeBasedActivity"".""Description"" as Fee_Based_Activity#(lf), ""tblPOEOLicenceFeeBasedActivity"".""PrimaryFlag"" as PrimaryFBA#(lf), ""tblInstrument"".""DateIssued"" as DateIssued#(lf), ""tblAddress"".""Suburb"" as LocationSuburb#(lf), ""tblAddress"".""StateCode"" as LocationState#(lf)FROM (((((((((((""PALMSDB"".""dbo"".""tblPOEOLicence"" ""tblPOEOLicence"" INNER JOIN ""PALMSDB"".""dbo"".""tblInstrument"" ""tblInstrument"" ON ""tblPOEOLicence"".""InstrumentID""=""tblInstrument"".""InstrumentID"") INNER JOIN ""PALMSDB"".""dbo"".""tblPOEOLicenceFeeBasedActivity"" ""tblPOEOLicenceFeeBasedActivity"" ON ""tblPOEOLicence"".""InstrumentID""=""tblPOEOLicenceFeeBasedActivity"".""InstrumentID"") INNER JOIN ""PALMSDB"".""dbo"".""viewInstrumentAccountableParty"" ""viewInstrumentAccountableParty"" ON ""tblPOEOLicence"".""InstrumentID""=""viewInstrumentAccountableParty"".""InstrumentID"") INNER JOIN ""PALMSDB"".""dbo"".""tblInstrumentLocation"" ""tblInstrumentLocation"" ON ""tblPOEOLicence"".""InstrumentID""=""tblInstrumentLocation"".""InstrumentID"") INNER JOIN ""PALMSDB"".""dbo"".""tblLocation"" ""tblLocation"" ON ""tblInstrumentLocation"".""LocationID""=""tblLocation"".""LocationID"") INNER JOIN ""PALMSDB"".""dbo"".""tblLandTitle"" ""tblLandTitle"" ON ""tblLocation"".""LocationID""=""tblLandTitle"".""LocationID"") INNER JOIN ""PALMSDB"".""dbo"".""tblAddress"" ""tblAddress"" ON ""tblLocation"".""AddressID""=""tblAddress"".""AddressID"") LEFT OUTER JOIN ""PALMSDB"".""dbo"".""tblLandTitleLGA"" ""tblLandTitleLGA"" ON ""tblLandTitle"".""LandTitleID""=""tblLandTitleLGA"".""LandTitleID"") LEFT OUTER JOIN ""PALMSDB"".""dbo"".""tblLGA"" ""tblLGA"" ON ""tblLandTitleLGA"".""LGAID""=""tblLGA"".""LGAID"") INNER JOIN ""PALMSDB"".""dbo"".""tblFeeBasedActivity"" ""tblFeeBasedActivity"" ON ""tblPOEOLicenceFeeBasedActivity"".""FeeBasedActivityID""=""tblFeeBasedActivity"".""FeeBasedActivityID"") INNER JOIN ""PALMSDB"".""dbo"".""tblActivityGroup"" ""tblActivityGroup"" ON ""tblFeeBasedActivity"".""ActivityGroupID""=""tblActivityGroup"".""ActivityGroupID"") INNER JOIN ""PALMSDB"".""dbo"".""tblClassification"" ""tblClassification"" ON ""tblInstrument"".""InstrumentStatusID""=""tblClassification"".""ClassificationID""#(lf)"])'; my $regex = qr/(?>"")(\w*)/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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