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

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = 'id-DirectTrust. arc 1.3.6.1.4.1.41179 id-DirectTrustpolicies id-DirectTrust.(0) 1.3.6.1.4.1.41179.0 DirectTrust-CP 2.0 id-DirectTrustpolicies.(2.0) 1.3.6.1.4.1.41179.0.2.0 id-DirectTrust-LoAs id-DirectTrust.(1) 1.3.6.1.4.1.41179.1 DirectTrust ID LoA 1 id-DirectTrust-LoAs.(1) 1.3.6.1.4.1.41179.1.1 DirectTrust ID LoA 2 id-DirectTrust-LoAs.(2) 1.3.6.1.4.1.41179.1.2 DirectTrust ID LoA 3 id-DirectTrust-LoAs.(3) 1.3.6.1.4.1.41179.1.3 DirectTrust ID LoA 4 id-DirectTrust-LoAs.(4) 1.3.6.1.4.1.41179.1.4 DirectTrust ID IAL 1 id-DirectTrust-LoAs.(1) 1.3.6.1.4.1.41179.1.1 DirectTrust ID IAL 2 id-DirectTrust-LoAs.(5) 1.3.6.1.4.1.41179.1.5 DirectTrust ID IAL 3 id-DirectTrust-LoAs.(6) 1.3.6.1.4.1.41179.1.6 id-DirectTrust-Cat id-DirectTrust.(2) 1.3.6.1.4.1.41179.2 DirectTrust CE id-DirectTrust-Cat.(1) 1.3.6.1.4.1.41179.2.1 DirectTrust BA id-DirectTrust-Cat.(2) 1.3.6.1.4.1.41179.2.2 DirectTrust HE id-DirectTrust-Cat.(3) 1.3.6.1.4.1.41179.2.3 DirectTrust Patient id-DirectTrust-Cat.(4) 1.3.6.1.4.1.41179.2.4 DirectTrust NonDeclared id-DirectTrust-Cat.(5) 1.3.6.1.4.1.41179.2.5 id-DirectTrust-Dev id-DirectTrust.(3) 1.3.6.1.4.1.41179.3 DirectTrust Device id-DirectTrust-Dev.(1) 1.3.6.1.4.1.41179.3.1 id-DirectTrust-authLoAs id-DirectTrust.(6) 1.3.6.1.4.1.41179.6 DirectTrust Auth AAL 1 id-DirectTrust-auth-LoAs.(5) 1.3.6.1.4.1.41179.6.5 DirectTrust Auth AAL 2 id-DirectTrust-auth-LoAs.(6) 1.3.6.1.4.1.41179.6.6 DirectTrust Auth AAL 3 id-DirectTrust-auth-LoAs.(7) 1.3.6.1.4.1.41179.6.7 id-DirectTrust-Cont id-DirectTrust.(7) 1.3.6.1.4.1.41179.7 DirectTrust Content Commitment id-DirectTrust-Cont.(1) 1.3.6.1.4.1.41179.7.1'; my $regex = qr/(.*) ([\w\d\.\-\(\)]+) (\d(?:\.\d+){2,}$)/mp; my $subst = '\\3\\t\\2\\t\\1'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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