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 = 'Platelet Count : 297 10 ^ 3/c.mm150 - 450 Total T3 (Tri-iodothyronine) : 86.99 ng/dl 58 - 159 Bilirubin (Direct) SERUM 0.32 0 - 0.50 mg/dl Total Cholesterol SERUM 180.00 0 - 200 mg/dl Packed Cell Volume : 39.7 % 36.0 - 46.0 asd123 y Q P Age /Sex * 45Years / Female123asd Blood Sugar Fasting PLASMA 92 70 - 105 mg/dl Referred By : QUANTUM CORPORTAE HEALTH Age /Sex : 32 Years Male Packed Cell Volume : 39.7 % 36.0 - 46.0 Platelet Count : 341 10 * 3/c.mm150 - 400 Uric Acid SERUM 8.42* 3.50-7.20 mg/dl SERUM TOTAL CHOLESTEROL 180 mg/dl 123Desirable ESR :* 22 mm / thr. 0-12 Haemoglobin - 12.4 gm % 12.0 - 15.0 Erythrocytes : 4.30 mill/c.mm 3.8 - 4.8 MCHC :* 31.4 g/dl 31.5 - 34.5 MPV :* 8.7 fl 9.0 - 13.0 Neutrophils - 62 % 40 - 80 Eosinophils 4-3 % 1-6 ABO And RhD Typing : A - positive Poikilocytosis 5 * Referred By : Quantum Corportae Health Pvt Ltd Ace Sen seme . Yeas. / Female ^([A-Za-z./\\-\\(\\) ]+|^[A-Za-z0-9/\\-\\(]+) +([0-9.\\-]+) *([a-zA-Z/%1 ]*) +([0-9./\\-= ]+)* *([A-Za-z/]*) ^([A-Za-z./\\-\\(\\=><) ]+|^[A-Za-z0-9/\\-\\(]+) *([0-9.\\*-]+)([a-zA-Z./% ]*) +([0-9.\\-= ]+)* *([A-Za-z/]*)'; my $regex = qr/^([A-Za-z./\-\(\=><) ]+:?\*?|^[A-Za-z./\-\(\=><)0-9 ]+:+?|^[A-Za-z0-9/\-\(]+)? *?(([0-9\*]+)(\.|\-)*([0-9\*]+)*)([a-zA-Z./% ]*) ?([0-9.\-= ]+)? ?(?![0-9]+)([a-zA-Z./% ]+)?$/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