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"
"
g

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('([A-Z0-9-]+)\\.txt:NAME:\\s\\"module\\s\\w+\\s([0-9/]+)\\",\\sDESCR:\\s\\"(.+)\\"', 'g') const str = `RMAGPGE-PGBP01-01.txt:NAME: "module R0", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPGE-PGIG01-01.txt:NAME: "module R0", DESCR: "ASR 903 Route Switch Processor 1, Base Scale, 55Gbps" RMAGPGE-PGIG01-01.txt:NAME: "module R1", DESCR: "ASR 903 Route Switch Processor 1, Base Scale, 55Gbps" RMAGPUI-PLIG01-01.txt:NAME: "module R0", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPUI-PLIG01-01.txt:NAME: "module R1", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPUI-PLMD00-01.txt:NAME: "module R0", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPUI-PLMD00-01.txt:NAME: "module R1", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPUI-PLMI00-01.txt:NAME: "module R0", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGPUI-PLMI00-01.txt:NAME: "module R1", DESCR: "ASR 900 Route Switch Processor 2, Base Scale, 128Gbps" RMAGRJO-CGD01-01.txt:NAME: "module 0/RSP0/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-CGD01-01.txt:NAME: "module 0/RSP1/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-CGD01-01.txt:NAME: "module 0/0/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-CGD01-01.txt:NAME: "module 0/0/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/0", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module 0/0/1", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/3", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/4", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/6", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/0/1/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module 0/1/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-CGD01-01.txt:NAME: "module 0/1/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/0", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module 0/1/1", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/3", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/6", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/1/1/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module 0/2/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-CGD01-01.txt:NAME: "module 0/2/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/0", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/5", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/2/0/7", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module 0/3/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-CGD01-01.txt:NAME: "module 0/3/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/0", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/5", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-CGD01-01.txt:NAME: "module mau 0/3/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module 0/RSP0/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-GDL01-01.txt:NAME: "module 0/RSP1/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-GDL01-01.txt:NAME: "module 0/0/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-GDL01-01.txt:NAME: "module 0/0/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/0", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/1", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module 0/0/1", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/0", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/3", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/4", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/0/1/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module 0/1/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-GDL01-01.txt:NAME: "module 0/1/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/0", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/1", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module 0/1/1", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/0", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/3", DESCR: "10GBASE-ZR SFP+, SMF 80km" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-GDL01-01.txt:NAME: "module mau 0/1/1/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-MRT01-01.txt:NAME: "module 0/RSP0/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-MRT01-01.txt:NAME: "module 0/RSP1/CPU0", DESCR: "ASR9K Route Switch Processor with 440G/slot Fabric and 12GB" RMAGRJO-MRT01-01.txt:NAME: "module 0/0/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-MRT01-01.txt:NAME: "module 0/0/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/0", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/1", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/0/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-MRT01-01.txt:NAME: "module 0/0/1", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/0", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/2", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/3", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/4", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/5", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/6", DESCR: "10GBASE-ER 1550nm SMF 40KM" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/0/1/7", DESCR: "10GBASE-LR SFP+ Module for SMF" RMAGRJO-MRT01-01.txt:NAME: "module 0/1/CPU0", DESCR: "160G Modular Linecard, Service Edge Optimized" RMAGRJO-MRT01-01.txt:NAME: "module 0/1/0", DESCR: "ASR 9000 8-port 10GE Modular Port Adapter" RMAGRJO-MRT01-01.txt:NAME: "module mau 0/1/0/0", DESCR: "10GBASE-LR SFP+ Module for SMF" `; // 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