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

r"
"
gmi

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('^[a-z]+[0-9/\\(\\)G]+\\s+.+\\n', 'gmi') const str = `E1 0/2/14 down down E1 0/2/15 down down GE0/0/0 down down GE0/3/0(10G) up up Conexao ao Anel AGG RMAGSRM-STRM06-01 GigabitEthernet0/4/0 GE0/3/1(10G) down down GE0/4/0(10G) up up Conexao ao Anel AGG RMCOSRM0101 GigabitEthernet0/3/0 GE0/4/1(10G) down down GE0/7/0 up up Conexao ao Anel ACC RMACSRM-STRM10-01 GigabitEthernet0/3/2 GE0/7/1 down down GE0/7/2 down down GE0/7/3 down down GE0/7/4 down down GE0/7/5 down down GE0/7/6 down down GE0/7/7 down down GE0/8/0 up up Conexao ao Anel ACC RMACSRM-STRM04-01 GigabitEthernet0/3/3 GE0/8/1 down down GE0/8/2 down down GE0/8/3 down down GE0/8/4 down down GE0/8/5 down down GE0/8/6 up down GE0/8/6.6 up up Conexao ao Servico 3G-<SRMSRMCPL113657>-<PA1808> GE0/8/7 down down Loop0 up up(s) Loopback Gerencia Loop2147483647 up up(s) DCN loopback interface NULL0 up up(s) S0/2/0:0 up up S0/5/0/1:1 down down S0/5/0/17:1 down down S0/5/0/33:1 down down S0/5/0/49:1 down down Mg0/RSP0/CPU0/1 admin-down admin-down Te0/2/0/0 up up Conexao ao RMCORJO0102 GE5/0/0 Te0/2/0/1 up up Conexao ao RTOCRJO0101 [Te0/1/0/6] Te0/2/0/2 up up Conexao RMCORJO0101 Te0/0/0/2 Te0/2/0/3 up up Conexao ao LTE-TIM - PTN -ANEL01 Te0/2/0/3.2001 up up CONEXAO ^\`eNB Te0/2/0/3.2002 up up CONEXAO - eNB Te0/2/0/3.2003 up up Conexao ao - eNB Te0/2/0/3.2004 up up Conexao ao - eNB Te0/2/0/3.2005 up up Conexao ao - eNB Te0/2/0/3.2006 up up Conexao ao - eNB Gi0/3/1/5 up up "Conexao ao RTISRJO0301 [Gig0/0/0] " Gi0/3/1/6 up up Conexao ao IPX COMFONE - IPX SERVICES - CPE LOCAL - 120 Mbps Gi0/3/1/6.201 up up Conexao ao IPX COMFONE - SIGNALING/DIAMETER - 1 Mbps Gi0/3/1/6.202 up up Conexao ao IPX COMFONE - SIGNALING/SS7 - 2 Mbps Gi0/3/1/6.203 up up Conexao ao IPX COMFONE - 2/3/4G ROAMING/GRX - 60 Mbps Gi0/3/1/7 up up Conexao ao OI - Link LAB TIM/OI - ID OI RJOSL8320483 Gi0/3/1/7.4000 up up RAN Sharing LTE OI - TIM [1000Mbps] Gi0/3/1/8 up up "Conexao ao SMS CLARO" Gi0/3/1/8.252 up up PEERING Conexao ao SMS CLARO - Trail RJORJOCPL062543 Accid 57807 Gi0/3/1/9 admin-down admin-down Gi0/3/1/10 admin-down admin-down `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions