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('[\\w-]+\\.txt:route-policy STATIC_TO_BGP|[\\w-]+\\.txt-end-policy', 'g') const str = `RMAGSPO-SAUT01-01.txt:route-policy STATIC_TO_BGP RMAGSPO-SAUT01-01.txt- if tag eq 40002 then RMAGSPO-SAUT01-01.txt- set community (26615:1000, 26615:51100, 26615:30000, 26615:1401, 26615:8012, 65402:9003, 65402:40002) RMAGSPO-SAUT01-01.txt- set origin igp RMAGSPO-SAUT01-01.txt- endif RMAGSPO-SAUT01-01.txt-end-policy RMAGSPO-SAUT01-01.txt-! RMAGSPO-SAUT01-01.txt-route-policy GERENCIA_UBB_STATIC_TO_BGP RMAGSPO-SAUT01-01.txt- if tag eq 30210 then -- RMAGSPO-SNE01-01.txt:route-policy STATIC_TO_BGP RMAGSPO-SNE01-01.txt- if tag eq 40002 then RMAGSPO-SNE01-01.txt- set community (26615:1000, 26615:51100, 26615:30000, 26615:1401, 26615:8012, 65402:9008, 65402:40002) RMAGSPO-SNE01-01.txt- set origin igp RMAGSPO-SNE01-01.txt- elseif tag eq 402 then RMAGSPO-SNE01-01.txt- set community (26615:1000, 26615:51100, 26615:30000, 26615:1301, 26615:8011, 65402:9008, 65402:40002) RMAGSPO-SNE01-01.txt- set origin igp RMAGSPO-SNE01-01.txt- endif RMAGSPO-SNE01-01.txt-end-policy -- RMAGSPO-SPLJ05-01.txt:route-policy STATIC_TO_BGP RMAGSPO-SPLJ05-01.txt- if tag eq 40002 then RMAGSPO-SPLJ05-01.txt- set community (26615:1000, 26615:51100, 26615:1301, 26615:8011, 65402:9006, 65402:40002, 26615:30000) RMAGSPO-SPLJ05-01.txt- set origin igp RMAGSPO-SPLJ05-01.txt- endif RMAGSPO-SPLJ05-01.txt-end-policy RMAGSPO-SPLJ05-01.txt-! RMAGSPO-SPLJ05-01.txt-route-policy GERENCIA_UBB_STATIC_TO_BGP RMAGSPO-SPLJ05-01.txt- if tag eq 30210 then -- RMAGSPO-SPVC03-01.txt:route-policy STATIC_TO_BGP RMAGSPO-SPVC03-01.txt- if tag eq 40002 then RMAGSPO-SPVC03-01.txt- set community (26615:1000, 26615:1401, 26615:51100, 26615:8012, 65402:9005, 65402:40002, 26615:30000) RMAGSPO-SPVC03-01.txt- set origin igp RMAGSPO-SPVC03-01.txt- elseif tag eq 40003 then RMAGSPO-SPVC03-01.txt- set community (26615:1000, 26615:1301, 26615:51100, 26615:8011, 65402:9005, 65402:40002, 26615:30000) RMAGSPO-SPVC03-01.txt- set origin igp RMAGSPO-SPVC03-01.txt- endif RMAGSPO-SPVC03-01.txt-end-policy -- RMAGSPO-SPVF06-01.txt:route-policy STATIC_TO_BGP RMAGSPO-SPVF06-01.txt- if tag eq 40002 then RMAGSPO-SPVF06-01.txt- set community (26615:1000, 26615:30000, 26615:51100, 26615:1301, 26615:8011, 65402:9004, 65402:40002) RMAGSPO-SPVF06-01.txt- set origin igp RMAGSPO-SPVF06-01.txt- endif RMAGSPO-SPVF06-01.txt-end-policy RMAGSPO-SPVF06-01.txt-! RMAGSPO-SPVF06-01.txt-route-policy GERENCIA_UBB_STATIC_TO_BGP RMAGSPO-SPVF06-01.txt- if tag eq 30210 then -- RMDISPO-MSO01-01.txt:route-policy STATIC_TO_BGP RMDISPO-MSO01-01.txt- if tag eq 40002 then RMDISPO-MSO01-01.txt- set community (26615:1000, 26615:51100, 26615:1401, 26615:8012, 65402:9002, 65402:40002, 26615:30000) RMDISPO-MSO01-01.txt- set origin igp RMDISPO-MSO01-01.txt- endif RMDISPO-MSO01-01.txt-end-policy RMDISPO-MSO01-01.txt-! RMDISPO-MSO01-01.txt-route-policy RMS-IN-FTTS-IPV4 RMDISPO-MSO01-01.txt- pass -- RTBARJO0202.txt:route-policy STATIC_TO_BGP RTBARJO0202.txt- if tag eq 51000 then RTBARJO0202.txt- set community (26615:51000, 26615:8021, 26615:9070, 26615:1201, 26615:30000) RTBARJO0202.txt- set origin igp RTBARJO0202.txt- endif RTBARJO0202.txt-end-policy RTBARJO0202.txt-! RTBARJO0202.txt-route-policy voip_migrados RTBARJO0202.txt- if destination in prefix_voip_migrados then -- RTBARJO0202.txt:route-policy STATIC_TO_BGP_IPV6 RTBARJO0202.txt- if tag eq 1000 then RTBARJO0202.txt- set community (26615:8021, 26615:9070, 26615:1000) RTBARJO0202.txt- set origin igp RTBARJO0202.txt- elseif tag eq 41000 then RTBARJO0202.txt- set community (26615:8021, 26615:9070, 26615:1201, 26615:51000, 26615:30000) RTBARJO0202.txt- set origin igp RTBARJO0202.txt- endif RTBARJO0202.txt-end-policy -- RTBASPO0302.txt:route-policy STATIC_TO_BGP RTBASPO0302.txt- if tag eq 41000 then RTBASPO0302.txt- set community (26615:41000, 26615:8012, 26615:9087, 26615:51000, 26615:1401, 26615:30000) RTBASPO0302.txt- set origin igp RTBASPO0302.txt- endif RTBASPO0302.txt-end-policy RTBASPO0302.txt-! RTBASPO0302.txt-route-policy voip_migrados RTBASPO0302.txt- if destination in prefix_voip_migrados then -- RTBASPO0302.txt:route-policy STATIC_TO_BGP_IPV6 RTBASPO0302.txt- if tag eq 1000 then RTBASPO0302.txt- set community (26615:8012, 26615:9087, 26615:1401, 26615:51000, 26615:30000) RTBASPO0302.txt- set origin igp RTBASPO0302.txt- endif RTBASPO0302.txt-end-policy RTBASPO0302.txt-! RTBASPO0302.txt-route-policy GERENCIA_UBB_STATIC_TO_BGP RTBASPO0302.txt- if tag eq 30210 then `; // 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