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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = '0000000000000000000020180209003010110001 00EXTVVD00000000000000000000000 00000000000000000000000 00000000000000000 000000000000000000000000000000000000000000000000 0000000000 000000000000000 000000000000000000000000000000000000000000 0000BALTES 00 BALTES 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 123 '; my $regex = qr/(?<PMNSEJ>.{10})(?<PMMRN>.{10})(?<PMDPSD>.{8})(?<PMDPSA>.{2})(?<PMCAMI>.{6})(?<PMNIJO>.{4})(?<PMCLI4>.{4})(?<PMCURG>.{1})(?<PMNRPR>.{8})(?<PMNRPR2>.{8})(?<PMNRPR3>.{8})(?<PMINDC>.{4})(?<PMMTX1>.{3})(?<PMREFP>.{8})(?<PMDDEM>.{8})(?<PMMDEM>.{8})(?<PMNOPR>.{1})(?<PMCSP1>.{2})(?<PMCSP2>.{2})(?<PMCSP3>.{2})(?<PMFLG1>.{1})(?<PMFLG2>.{1})(?<PMFLG3>.{1})(?<PMFLG4>.{1})(?<PMDAJC>.{8})(?<PMNOTK>.{9})(?<PMMODP>.{1})(?<PMINDP>.{4})(?<PMTPPE>.{8})(?<PMTCHE>.{8})(?<PMNOTKR>.{9})(?<PMACOT2>.{8})(?<PMDAFA>.{8})(?<PMNRUN>.{3})(?<PMCCLO>.{1})(?<PMRELA>.{6})(?<PMCHOPER>.{1})(?<PMPOSU>.{3})(?<PMCLM>.{2})(?<PMSLM>.{2})(?<PMHMPR>.{4})(?<PMDACO>.{8})(?<PMEPRO>.{3})(?<PMEXTP>.{1})(?<PMIMPL>.{12})(?<PMIMPNQE>.{13})(?<PMDPRO>.{8})(?<PMDRECD>.{8})(?<PMNRPROG>.{6})(?<PMRUNE>.{7})(?<PMNPIE>.{10})(?<PMNRPASS>.{4})(?<PMAPI>.{8})(?<PMCS34>.{10})(?<PMMVTREF>.{1})(?<PMBATT>.{15})(?<PMBATTS>.{2})(?<PMBATTE>.{1})(?<PMUSER>.{10})(?<PMRESE>.{30})(?<PMRESA1>.{10})(?<PMRESA2>.{12})(?<PMTBPE>.{8})(?<PMTRME>.{8})(?<PMTMPE>.{8})(?<PMOSUE>.{7})(?<PMTMUE>.{8})(?<PMTCAE>.{8})(?<PMTPAE>.{8})(?<PMMTBP>.{7})(?<PMMTRM>.{7})(?<PMMTMP>.{7})(?<PMMOSU>.{6})(?<PMMTMU>.{7})(?<PMMTCA>.{7})(?<PMMTPA>.{7})(?<PMMTPP>.{7})(?<PMMTCH>.{7})(?<PMNOTIMPL>.{12})(?<Filler>.{35})(?<Particularites>.{100})/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