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 = 'SLN 4 GRP 662 STYP \'TZ\' SNO 1037 DRX -3.41018E-15 2.25685E-15 -1 XFLG \'PLA\' SLNB X1 -71629.6763 -89524.0401 34193.7197 X2 -70145.9264 -91487.9275 34193.7197 SLN 6 GRP 662 STYP \'TZ\' SNO 1037 DRX -3.41018E-15 2.25685E-15 -1 XFLG \'PLA\' SLNB X1 -68645.9265 -89524.0401 34193.7197 X2 -67145.9265 -91487.9275 34193.7197 SLN 8 GRP 662 STYP \'TZ\' SNO 1037 DRX -3.41018E-15 2.25685E-15 -1 XFLG \'PLA\' SLNB X1 -65780.9266 -89524.0401 34193.7197 X2 -64280.9267 -91487.9275 34193.7197 SLN 10 GRP 662 STYP \'TZ\' SNO 1037 DRX -3.41018E-15 2.25685E-15 -1 XFLG \'PLA\' SLNB X1 -62780.9267 -89524.0401 34193.7197 X2 -61280.9268 -91487.9275 34193.7197 SLN 12 GRP 662 STYP \'TZ\' SNO 1037 DRX 3.41018E-15 2.25685E-15 -1 XFLG \'PLA\' SLNB X1 -74597.1762 -89524.0401 34193.7197 X2 -76080.9261 -91487.9275 34193.7197 SLN 15 GRP 662 STYP \'TZ\' SNO 1037 DRX -0.218907 0.519243 -0.826115 XFLG \'PLA\' SLNB X1 -71629.6763 -95007.3548 31588.4632 X2 -73113.4262 -91487.9275 34193.7197 SLN 16 GRP 662 STYP \'TZ\' SNO 1037 DRX 0.218907 0.519243 -0.826115 XFLG \'PLA\' SLNB X1 -70145.9264 -91487.9275 34193.7197 X2 -71629.6763 -95007.3548 31588.4632 SLN 17 GRP 662 STYP \'TZ\' SNO 1037 DRX -0.215802 0.515972 -0.828976 XFLG \'PLA\' SLNB X1 -68645.9265 -95074.3499 31570.9694 X2 -70145.9264 -91487.9275 34193.7197 SLN 18 GRP 662 STYP \'TZ\' SNO 1037 DRX 0.215802 0.515972 -0.828976 XFLG \'PLA\' SL'; my $regex = qr/[Ss][Ll][Nn]\s+\d+\s+[Gg][Rr][Pp]\s+\d+\s+[S][T][Y][P]\s+['][T][Z][']\s+[Ss][Nn][Oo]\s+\d+\s+/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