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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

re = /^(\%.*|Command rejected.*)/m str = '**State Acronym: H - Healthy, W - Warning, C - Critical Resource Usage Max Warning Critical State ---------------------------------------------------------------------------------------------------- RP0 (ok, active) H Control Processor 29.42% 100% 80% 90% H DRAM 2840MB(72%) 3938MB 88% 93% H bootflash 1889MB(69%) 2753MB 70% 90% H ESP0(ok, active) H QFP H DRAM 81237KB(41%) 196608KB 85% 95% H IRAM 207KB(10%) 2048KB 85% 95% H CPU Utilization 2.00% 100% 90% 95% H Load Average Slot Status 1-Min 5-Min 15-Min RP0 Healthy 1.24 1.20 1.23 Memory (kB) Slot Status Total Used (Pct) Free (Pct) Committed (Pct) RP0 Healthy 4033104 2909060 (72%) 1124044 (28%) 3749844 (93%) CPU Utilization Slot CPU User System Nice Idle IRQ SIRQ IOwait RP0 0 3.51 4.89 0.00 90.10 0.95 0.53 0.00 1 2.96 4.55 0.00 90.98 1.06 0.42 0.00 2 21.93 2.01 0.00 75.28 0.67 0.09 0.00 3 29.17 34.41 0.00 25.93 10.09 0.37 0.00 2222233333111111111111111111111111111111 111112222222222 100 90 80 70 60 50 40 30 20 10 0....5....1....1....2....2....3....3....4....4....5....5....6 0 5 0 5 0 5 0 5 0 5 0 CPU% per second (last 60 seconds) 1 1 1 1 1 1 1 439546515464943339403403334255420343303354853430442395424873 100 90 80 70 60 50 40 30 20 10 ** **#* * # * * * *** * * * ** * ** * 0....5....1....1....2....2....3....3....4....4....5....5....6 0 5 0 5 0 5 0 5 0 5 0 CPU% per minute (last 60 minutes) * = maximum CPU% # = average CPU% % Ambiguous command % Invalid input detected at \'^\' marker % Bad Mask /xx for address X.X.X.X % X.X.X.X overlaps with GigabitEthernet0/1 Command rejected: Conflict between \'nonegotiate\' and \'dynamic\' status % Configuration of multiple subinterfaces of the same main interface with the same VID is not permitted % Configuring IP routing on a LAN subinterface is only allowed if that subinterface is already configured as part of a VLAN % Inconsistent address and mask % Invalid next hop address (it\'s this router) ' # Print the match result str.scan(re) do |match| puts match.to_s end

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