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

r"
"
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'H-4WEH62HE5XF/10EG24N9S2K4 H-4WEH62HD5XF/OF10EG220N9SK4/B10V H-4WEH62HH5XF/10EG24N9K4 '; my $regex = qr/^(?P<operating_pressure>H)(?P<sep_1>-)(?P<number_of_main_ports>4)(?P<unit_type>W)(?P<actuation_type>EH|H)(?P<unit_size>62)(?P<spool_feedback_main_stage>H|)(?P<spool_symbol>C|D|K|Z|E|F|G|H|J|L|M|Q|R|S|T|U|V|W)(?P<unit_series>5X)(?P<mounting_type>F|)(?P<sep_2>/)(?P<spool_feedback>OF|O)(?P<pilot_valve>10)(?P<type_of_solenoid>A|L)(?P<solenoid_in_ac_or_dc_version>G|W)(?P<voltage_of_solenoid>220|195|180|127|120|110|96|60|42|24|12)(?P<voltage_rectifier>R|-|)(?P<manual_override_unit>Y|)(?P<spool_position_monitoring>Y|)(?P<unit_for_time_adjustment>S2|S|)(?P<electrical_connection>Z5L|Z2L|Z1L|DKL|DZL|DL|DZ|DK|ZL|KL|Z5|Z4|Z2|Z1|D|L|Z|K|)(?P<sep_3>/)(?P<additional_equipment>17|16|15|14|13|12|11|10)(?P<orifice_positon>B|)(?P<orifice_diameter>15|12|11|10|08|)(?P<seal_material>V|)(?P<additional_details>)$ /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