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

/
/
gms

Test String

Code Generator

Language

Generated Code

const regex = /(?<=at point, )(X=(?:\d|\.)+) +\K(Y=(?:\d|\.)+).*?\K(value \w+)\R +\K(tag \w+)\K/gms; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<=at point, )(X=(?:\\d|\\.)+) +\\K(Y=(?:\\d|\\.)+).*?\\K(value \\w+)\\R +\\K(tag \\w+)\\K', 'gms') const str = `[ AutoCAD - Thu Sep 03 15:59:09 2020 ]---------------------------------------- Command: LIST Select objects: Specify opposite corner: 468 found Select objects: BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal BLOCK REFERENCE Layer: "layer1" Space: Model space Handle = 12345 Block Name: "Block" at point, X=1378.4556 Y=1314.2124 Z= 0.0000 X scale factor: 16.5000 Y scale factor: 16.5000 rotation angle: 160.67 Z scale factor: 266.0000 Scale uniformly: No Allow exploding: Yes ATTRIBUTE Layer: "layer1" Space: Model space Handle = 12345 Style = "STANDARD" Annotative: No Font file = default.shx substituted by default.shx start point, X=1365.1222 Y=1319.6510 Z= 0.0000 height 3.0000 value 2999 tag THINGY rotation angle 340.67 width scale factor 1.0000 obliquing angle 0.00 flags normal generation normal`; // 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