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

Substitution

Processing...

Code Generator

Language

Generated Code

re = /=+|GOLIATH/ str = '===================================================================================== GOLIATH ===================================================================================== *** GOLIATH BACKUP CHECK *** GOLIATH BACKUP CHECK *** GOLIATH BACKUP CHECK *** ====]] GOLIATH Backup Check Results [[==== --] Remote Reachability Test Pings were NOT successful to 172.16.158.1 from remote router uscmcraudfl04r. USCMCRAUDFL04R#ping 172.16.158.1 source FastEthernet0 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.158.1, timeout is 2 seconds: Packet sent with a source address of 172.16.112.1 ..... Success rate is 0 percent --] Backup Device Test GOLIATH did not detect any backup devices connected to the router. --] Back-to-Back Test No SMARTS Back-to-Back connections detected. GOLIATH did not detect any iBGP connections for this device. --] ISDN Test No ISDN interfaces detected on router or B2B routers. =====================================================================================' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html