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

/
/
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)\s*src\s*:\s*"(.*?)"`) var str = `<script type='text/javascript'>var holaplayer; window.hola_player({ player: '#hola', share: false, poster: 'https://s475.clipwatching.com/i/02/02889/onou5kiza8cr.jpg', sources: [{src: "https://s475.clipwatching.com/zx5x4sn47f2txcne4zqsjghf2y3o4r2okiasq6h2zzssd7xctj7bkkn3p7mq/v.mp4", type: "video/mp4", res: 360, label: "360"}], preload: 'auto', thumbnails:{ vtt:'https://clipwatching.com/dl?op=get_slides&length=1440&url=https://s475.clipwatching.com/i/02/02889/onou5kiza8cr0000.jpg' },ads: { adTagUrl: 'https://www.movcpm.com/watch.xml?key=383cac3ff2358ef864279f1c5e1053ba' }, videojs_options: { html5: { hlsjsConfig: { debug: false, startLevel: 1, maxBufferLength: 30, maxBufferSize: 10*1024*1024, maxMaxBufferLength: 600, capLevelToPlayerSize: true, } }, }, }, function(player){` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/