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 $str = 'ajnxaslndsa;ndaJDASDNsadnKDNadk;NADK\'nadkAnaskdmaskdnajfbajfnakdnaj;knasjnakdna;jkdna;nda;dna;kdnas;dkns so as sadasldka aldaskl . asdas asd 5,400 cgy 40.00 cgy 4 cgy gleason score 6/10(4+3), = 7 ) 1.1- 0.6,df 2,4-3,6 asdf 4+5+6 gleason\'s pattern: 2+3, 5 gleason score = 5(2+3) score 1+2, (score 7) gleason Dec 2011-23 jan 500,000.012 cgy sdfsfsodm sdfsd f sdfsd afdas. s adasas dasd as asdasdaskd askdm askdmas\'ljdnas;das.ndaskjndajkndWJDNAksz (?P<core1>(?i)[A-Z0-9]+)[\\s]?((?i)out of|of|\\/)[\\s]?(?P<core2>(?i)[A-Z0-9]+)[\\s]?(?:(?i)core[s]?|needle core[s]?) (?P<core1>(?i)[A-Z0-9]+)[\\s]?((?i)core[s]? out of)[\\s]?(?P<core2>(?i)[A-Z0-9]+) (?:(?i)involving)[\\s]?(?P<core1>(?i)[A-Z0-9]+)[\\s]?(?:(?i)core[s]?|needle core[s]?) 1 of 3 core one of three cores involving 1/2 cores involving five of six cores two of the cores one of multiple cores 1 of multiple cores two of 4 cores 5 of six cores (1/8 needle cores) (3/7 cores) one out of six cores two cores out of two 1 core out of 2 involving 1 core involving two cores gleason score 9, 4+5=9/10, PSA = 27.60, 8 specimens {0,1SDf00} 10% 20% (?<=(?i)gleason)[\\w\\s\\p{P}\\=]*[^0-9\\.\\+]*\\s*\\K(\\d)\\s*\\+\\s*(\\d)(?=\\D) (?<=(?i)gleason)[\\w\\s\\p{P}\\=]*[^0-9\\.\\+]*\\s*\\K(\\d)\\s*\\+\\s*(\\d)(?=\\D) (?<=(?i)gleason)[\\w\\s\\p{P}\\=]*[^0-9\\.\\-]*\\s*\\K(\\d)\\s*\\-\\s*(\\d)(?=\\D\\-) (?<=(?i)gleason)[\\w\\s\\p{P}\\=]*[^0-9\\.\\,\\#]*\\s*\\K(\\d)\\s*\\,\\s*(\\d)(?=\\D) [\\w\\s\\p{P}\\=]*[^0-9\\.\\+]*\\s*\\K(\\d)\\s*\\+\\s*(\\d)(?=\\D) [\\w\\s\\p{P}\\=]*[^0-9\\.\\-]*\\s*\\K(\\d)\\s*\\+\\s*(\\d)(?=\\D\\-) (?<=[\\\\s])\\\\s*|^\\\\s+|\\\\s+$ '; my $regex = qr/(?P<core1>(?i)[A-Z0-9]+)[\s]?((?i)out of|of|\/)[\s]?(?P<core2>(?i)[A-Z0-9]+)[\s]?(?:(?i)core[s]?|needle core[s]?)/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