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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = ' #怎么玩 #有哪里好玩的 #有哪里好玩 #什么好玩的 #哪儿好玩 #什么好玩的地方 #有什么好玩的 #有哪好玩的 #都有什么好玩的 #有什么好地方 #啥好玩的 #有什么可玩的 #有什么好玩的地 #有啥可玩的 #有哪好玩 #什么景点 #有什么好玩的呀 #有什么好玩 #有哪些好玩的 #有哪里好玩的地方 #有啥好玩的没 #都有哪些好玩的 #有什么风景区 #有什么好景点 #有什么好玩的阿 #有哪里好玩呀 #有什么好玩的地儿 #有什么地方去 #有什么好玩的没 #有啥好玩的不 #哪儿好玩儿 #有什么可玩儿的 #哪儿好玩呀 #有啥好玩的地方 #什么好玩的呀 #有什么好玩的地方 #有啥子好玩的 #什么好玩儿的 #都有什么景点 去#有什么好玩的地方 我想去#有什么好玩儿的 去#有什么好玩的呀 去#有什么好玩 去#旅游怎么样 去#玩什么 去#玩 去#玩怎么样 #去哪里好玩 #有什么玩的 #有好玩的么 #什么地方好玩 #攻略有吗 #好玩的地方有哪些 去#的攻略 #风景区 去#旅游 #周边游 #游玩攻略 #有什么可玩的 '; my $regex = qr/^我?(想|要)?(到|去)?#都?有?((哪(儿|里)?|(啥|什么|哪些|啥子))((好|可)玩儿?的?(地(方|儿)?)?|好?地(方|儿))去?|(怎么|咋)玩儿?|(什么|啥|哪些)好?((旅游|游玩)?(景点|攻略)|风景区|旅游区))(吗|呢|不|吧|嘛|么|呀|没|啊|阿)?$/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