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 = '<tr class="child "> <td>-12,777,460.8</td> <td>432.8</td> <td>-12,460.8</td> <td>-4.53</td> </tr> <tr class="child impair"> <td>2,389.0</td> <td>408.2</td> <td>2,389.0</td> <td>2.92</td> </tr> <tr class="child "> <td>2,395.6</td> <td>393.3</td> <td>2,395.6</td> <td>1.13</td> </tr> <tr class="child impair"> <td>2,357.4</td> <td>413.6</td> <td>2,357.4</td> <td>0.87</td> </tr> <tr class="child "> <td>2,465.6</td> <td>405.6</td> <td>2,465.6</td> <td>1.30</td> </tr> <tr class="child impair"> <td>2,519.0</td> <td>412.0</td> <td>2,519.0</td> <td>7.63</td> </tr> <tr class="child "> <td>2,300.2</td> <td>571.9</td> <td>2,300.2</td> <td>28.33</td> </tr> <tr class="child impair"> <td>2,241.3</td> <td>888.4</td> <td>2,241.3</td> <td>44.00</td> </tr> <tr class="child "> <td>2,196.2</td> <td>914.8</td> <td>2,196.2</td> <td>50.02</td> </tr> <tr class="child impair"> <td>2,243.7</td> <td>920.3</td> <td>2,243.7</td> <td>43.27</td> </tr> <tr class="child "> <td>2,279.8</td> <td>721.7</td> <td>2,279.8</td> <td>33.96</td> </tr> <tr class="child impair"> <td>2,283.4</td> <td>730.6</td> <td>2,283.4</td> <td>32.09</td> </tr> <tr class="child "> <td>2,389.2</td> <td>623.8</td> <td>2,389.2</td> <td>33.16</td> </tr> <tr class="child impair"> <td>2,290.2</td> <td>593.7</td> <td>2,290.2</td> <td>34.00</td> </tr> <tr class="child "> <td>2,222.2</td> <td>711.0</td> <td>2,222.2</td> <td>37.51</td> </tr> <tr class="child impair"> <td>2,200.4</td> <td>1,052.5</td> <td>2,200.4</td> <td>44.70</td> </tr> <tr class="child "> <td>2,202.8</td> <td>1,060.6</td> <td>2,202.8</td> <td>50.02</td> </tr> <tr class="child impair"> <td>2,135.9</td> <td>993.9</td> <td>2,135.9</td> <td>50.73</td> </tr> <tr class="child "> <td>2,177.7</td> <td>1,028.5</td> <td>2,177.7</td> <td>54.04</td> </tr> <tr class="child impair"> <td>2,092.6</td> <td>1,095.5</td> <td>2,092.6</td> <td>48.24</td> </tr> <tr class="child "> <td>1,980.3</td> <td>586.2</td> <td>1,980.3</td> <td>36.83</td> </tr> <tr class="child impair"> <td>2,029.0</td> <td>600.0</td> <td>2,029.0</td> <td>33.84</td> </tr> <tr class="child "> <td>1,995.1</td> <td>513.9</td> <td>1,995.1</td> <td>30.41</td> </tr> <tr class="child impair"> <td>1,990.6</td> <td>470.1</td> <td>1,990.6</td> <td>12.00</td> </tr>'; my $regex = qr/(?:-?(?:\d+?,)+)?-?\d+\.\d+/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