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"
"
gs

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'VERSION "" NS_ : NS_DESC_ CM_ BA_DEF_ BA_ VAL_ CAT_DEF_ CAT_ FILTER BA_DEF_DEF_ EV_DATA_ ENVVAR_DATA_ SGTYPE_ SGTYPE_VAL_ BA_DEF_SGTYPE_ BA_SGTYPE_ SIG_TYPE_REF_ VAL_TABLE_ SIG_GROUP_ SIG_VALTYPE_ SIGTYPE_VALTYPE_ BO_TX_BU_ BA_DEF_REL_ BA_REL_ BA_DEF_DEF_REL_ BU_SG_REL_ BU_EV_REL_ BU_BO_REL_ BS_: BU_: BO_ 777 VBOX_9: 8 Vector__XXX SG_ Longitude_48bit : 7|48@0- (1E-07,0) [0|0] "minutes" Vector__XXX BO_ 776 VBOX_8: 8 Vector__XXX SG_ Latitude_48bit : 7|48@0- (1E-07,0) [0|0] "minutes" Vector__XXX SG_ Kalman_filter_status : 56|1@0+ (1,0) [0|1] "" Vector__XXX BO_ 774 VBOX_6: 8 Vector__XXX SG_ Vel_Quality : 7|16@0- (0.01,0) [0|0] "km/h" Vector__XXX BO_ 773 VBOX_5: 8 Vector__XXX SG_ Trig_Vel_Mph : 55|16@0+ (0.0115078,0) [0|754.163673] "Mph" Vector__XXX SG_ Trig_Vel_Kmh : 55|16@0+ (0.01852,0) [0|1213.7082] "Km/h" Vector__XXX SG_ Trig_time : 39|16@0+ (0.01,0) [0|655.35] "Secs" Vector__XXX SG_ Distance : 7|32@0+ (7.8125E-05,0) [0|335544] "Metres" Vector__XXX BO_ 772 VBOX_4: 8 Vector__XXX SG_ Lateral_acceleration : 55|16@0- (0.01,0) [-327.68|327.67] "G" Vector__XXX SG_ Longitudinal_acceleration : 39|16@0- (0.01,0) [-327.68|327.67] "G" Vector__XXX SG_ Trig_Dist : 7|32@0+ (7.8125E-05,0) [0|335544] "Metres" Vector__XXX BO_ 771 VBOX_3: 8 Vector__XXX SG_ DGPS : 61|1@0+ (1,0) [0|0] "On" Vector__XXX SG_ Brake_trigger : 60|1@0+ (1,0) [0|0] "On" Vector__XXX SG_ Vertical_Velocity : 31|16@0- (0.01,0) [0|655.36] "m/s" Vector__XXX SG_ Altitude_WGS84 : 7|24@0- (0.01,0) [0|42949700] "metres" Vector__XXX BO_ 770 VBOX_2: 8 Vector__XXX SG_ Velocity_Mph : 39|16@0+ (0.0115078,0) [0|754.163673] "Mph" Vector__XXX SG_ Heading : 55|16@0+ (0.01,0) [0|359.99] "Degrees" Vector__XXX SG_ Velocity_Kmh : 39|16@0+ (0.01852,0) [0|1213.7082] "Km/h" Vector__XXX SG_ Longitude : 7|32@0- (1E-05,0) [-21474.83648|21474.83647] "Minutes" Vector__XXX BO_ 769 VBOX_1: 8 Vector__XXX SG_ Latitude : 39|32@0- (1E-05,0) [-21474.83648|21474.83647] "Minutes" Vector__XXX SG_ Time_Since_Midnight : 15|24@0+ (0.01,0) [0|0] "Seconds" Vector__XXX SG_ Sats : 7|8@0+ (1,0) [0|12] "Sats" Vector__XXX '; my $regex = qr/ SG_ (\w+) : (\d+)\|(\d+)@[01][+-] \(([0-9E\-\+\.]*),([0-9E\-\+\.]*)\) \[[0-9E\-\+\.]*\|[0-9E\-\+\.]*\] "([^"]*)" Vector__XXX/sp; 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