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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<ul> <li><a href="#symbols">Symbol report</a></li> <ul> <li><a href="#symbolsConsistency">Consistency</a></li> <li><a href="#symbolCharacteristics">Symbol characteristics</a></li> <li><a href="#basicSymbols">Display of basic symbols</a></li> <ul> <li>Pg_1_qds_Bin_Indicator_2</li> <ul> <li>[QDSConsistency.report.field.logicIndicator.descriptionalignment] = (Right)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptiontextcolor] = (Color {0, 0, 0, 255})</li> <li>[QDSConsistency.report.field.logicIndicator.isdescriptiondisplayed] = (true)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontstyle] = (Normal)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontposition] = (LEFT)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptiontext] = (v1)</li> <li>[QDSConsistency.report.field.logicIndicator.backgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.logicIndicator.digitnumber] = (8)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetfont] = (FONT1)</li> <li>[QDSConsistency.report.field.logicIndicator.shortname] = (Pg_1_qds_Bin_Indicator_2)</li> <li>[QDSConsistency.report.field.logicIndicator.precision] = (2)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetuserfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetuserfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetuserfontstyle] = (NORMAL)</li> <li>[QDSConsistency.report.field.analogIndicator.dynamicbackgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.analogIndicator.longname] = (Pg_1_qds_Bin_Indicator_2_v1)</li> <li>[QDSConsistency.report.field.logicIndicator.heith] = (32)</li> <li>[QDSConsistency.report.field.logicIndicator.weigth] = (50)</li> <li>[QDSConsistency.report.field.logicIndicator.poxX] = (352)</li> <li>[QDSConsistency.report.field.logicIndicator.poxY] = (116)</li> <li>[QDSConsistency.report.field.logicIndicator.valuealignment] = (Left)</li> <li>[QDSConsistency.report.field.logicIndicator.value_0] = (Off)</li> <li>[QDSConsistency.report.field.logicIndicator.value_1] = (On)</li> </ul> <li>Pg_1_qds_Bin_Indicator_3</li> <ul> <li>[QDSConsistency.report.field.logicIndicator.descriptionalignment] = (Right)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptiontextcolor] = (Color {0, 0, 0, 255})</li> <li>[QDSConsistency.report.field.logicIndicator.isdescriptiondisplayed] = (true)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontstyle] = (Normal)</li> <li>[QDSConsistency.report.field.logicIndicator.descriptionfontposition] = (LEFT)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptiontext] = (v1)</li> <li>[QDSConsistency.report.field.logicIndicator.backgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.logicIndicator.digitnumber] = (8)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetfont] = (FONT1)</li> <li>[QDSConsistency.report.field.logicIndicator.shortname] = (Pg_1_qds_Bin_Indicator_3)</li> <li>[QDSConsistency.report.field.logicIndicator.precision] = (2)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetuserfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.logicIndicator.widgetuserfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetuserfontstyle] = (NORMAL)</li> <li>[QDSConsistency.report.field.analogIndicator.dynamicbackgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.analogIndicator.longname] = (Pg_1_qds_Bin_Indicator_3_v1)</li> <li>[QDSConsistency.report.field.logicIndicator.heith] = (32)</li> <li>[QDSConsistency.report.field.logicIndicator.weigth] = (50)</li> <li>[QDSConsistency.report.field.logicIndicator.poxX] = (446)</li> <li>[QDSConsistency.report.field.logicIndicator.poxY] = (187)</li> <li>[QDSConsistency.report.field.logicIndicator.valuealignment] = (Left)</li> <li>[QDSConsistency.report.field.logicIndicator.value_0] = (Off)</li> <li>[QDSConsistency.report.field.logicIndicator.value_1] = (On)</li> </ul> </ul> <p><em>Analog indicator :</em></p> <ul> <li>Pg_1_qds_Ana_Indicator_1</li> <ul> <li>[QDSConsistency.report.field.analogIndicator.descriptionalignment] = (Right)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptiontextcolor] = (Color {0, 0, 0, 255})</li> <li>[QDSConsistency.report.field.analogIndicator.isdescriptiondisplayed] = (true)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptionfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptionfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptionfontstyle] = (Normal)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptionfontposition] = (LEFT)</li> <li>[QDSConsistency.report.field.analogIndicator.descriptiontext] = (v0)</li> <li>[QDSConsistency.report.field.analogIndicator.backgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.analogIndicator.digitnumber] = (8)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetfont] = (FONT1)</li> <li>[QDSConsistency.report.field.analogIndicator.shortname] = (Pg_1_qds_Ana_Indicator_1)</li> <li>[QDSConsistency.report.field.analogIndicator.precision] = (2)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetuserfontfamily] = (Arial)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetuserfontsize] = (11 pt)</li> <li>[QDSConsistency.report.field.analogIndicator.widgetuserfontstyle] = (NORMAL)</li> <li>[QDSConsistency.report.field.analogIndicator.dynamicbackgroundcolor] = (Color {238, 238, 238, 255})</li> <li>[QDSConsistency.report.field.analogIndicator.longname] = (Pg_1_qds_Ana_Indicator_1_v0)</li> <li>[QDSConsistency.report.field.analogIndicator.heith] = (32)</li>'; my $regex = qr/<li>(Pg_.*)<\/li>/p; 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