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 = '(A) 2016-10-23 +projectB $2016-10-03 to be completed as soon as possible @context_bar (A) 2016-11-01 +projectA $2016-09-25 job to complete @context @context_two (B) ? +houseworks $2016-10-04^2D,W lavoro importante &TAG_FOO &TAG_BAR 2016-12-15 +projectA#2 $2016-09-25 second job related to the same project @another_context ? +houseworks $2016-10-02^3D altro lavoro di casa @context_bar &TAG ? +projectA#3 $2016-09-25 third job of the same project @foo_context &WAIT ? +projectA#4 $2016-09-25 fourth job, needs third to be completed first 2016-11-23 $2015-06-23^4Y another job without project @context_foo @context_bar &TAG_A &TAG_B ? minimal job like email fra@me.com'; my $regex = qr/^(?:\((?P<imp>[A-Z])\)\ )?(?P<dued>(?:2[0-1][0-9]{2}\-(?:0[0-9]|1[0-2])\-(?:[0-2][0-9]|3[0-1]))|\?)\ (?:\+(?P<proname>[a-zA-Z0-9]+)(?:\#(?P<pronum>[0-9]+))?\ )?(?:\$(?P<startd>2[0-1][0-9]{2}\-(?:0[0-9]|1[0-2])\-(?:[0-2][0-9]|3[0-1]))(?:\^(?P<repeat>\d*(?:D|W|M|Y)(?:\,\d*(?:D|W|M|Y)+)*))?\ )?(?P<todo>.+?(?=(?:\ (?:\@|\&))|$))(?P<contexts>(?:\ \@\S+)*)(?P<tags>(?:\ \&\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