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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<div> <p style="text-align: left;">Style: <span style="float: right;">Casual</span></p> </div> <div> <p style="text-align: left;">Color: <span style="float: right;">float</span></p> </div> <div> <p style="text-align: left;">Pattern Type: <span style="float: right;">Letter</span></p> </div> <div> <p style="text-align: left;">Neckline: <span style="float: right;">Round Neck</span></p> </div> <div> <p style="text-align: left;">Length: <span style="float: right;">Regular</span></p> </div> <div> <p style="text-align: left;">Type: <span style="float: right;">Pullovers</span></p> </div> <div> <p style="text-align: left;">Details: <span style="float: right;">Frill</span></p> </div> <div> <p style="text-align: left;">Sleeve Length: <span style="float: right;">Long Sleeve</span></p> </div> <div> <p style="text-align: left;">Sleeve Type: <span style="float: right;">Drop Shoulder</span></p> </div> <div> <p style="text-align: left;">Season: <span style="float: right;">Spring/Fall</span></p> </div> <div> <p style="text-align: left;">Composition: <span style="float: right;">5% Spandex</span></p> </div> <div> <p style="text-align: left;">Composition: <span style="float: right;">95% Polyester</span></p> </div> <div> <p style="text-align: left;">Fabric: <span style="float: right;">Slight Stretch</span></p> </div> <div> <p style="text-align: left;">Fit Type: <span style="float: right;">Regular Fit</span></p> </div> <p></p> <table border="1"> <thead> <tr> <th>size</th> <th>Shoulder</th> <th>Bust</th> <th>Length</th> <th>Sleeve Length</th> <th>Bicep Length</th> <th>Cuff</th> </tr> </thead> <tbody> <tr> <td>XS</td> <td>63 cm</td> <td>104 cm</td> <td>63 cm</td> <td>51 cm</td> <td>45 cm</td> <td>17 cm</td> </tr> <tr> <td>S</td> <td>64 cm</td> <td>108 cm</td> <td>64 cm</td> <td>52 cm</td> <td>46 cm</td> <td>18 cm</td> </tr> <tr> <td>M</td> <td>65 cm</td> <td>112 cm</td> <td>65 cm</td> <td>53 cm</td> <td>47 cm</td> <td>19 cm</td> </tr> <tr> <td>L</td> <td>66 cm</td> <td>116 cm</td> <td>66 cm</td> <td>54 cm</td> <td>48 cm</td> <td>20 cm</td> </tr> </tbody> </table>'; my $regex = qr/(?i)(>[^<\/\nA-Za-z]{0,5})\Qfloat\E([^>\/\nA-Za-z]{0,5}<)/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