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

/
/
gmu

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?:([-‐‑‒–—―−⁃﹘﹣－])|(?:&(?:(?:#x(2d|201[0-5]|2212|2043|fe58|fe63|ff0d))|(?:#(45|820[89]|821[0123]|8722|8259|65112|65123|65293))|(hyphen|[nm]?dash|hybull|horbar|minus));?))`) var str = `This captures an entity even if it lacks the ';', which is commonly encountered in the wild. kbdash &#x2d; &#45; &#x2d &#45 -; - dash &#x2010; &dash; &#8208; &#x2010 &#8208 ‐; ‐ hyphen &#x2011; &hyphen; &#8209; &#x2011 &#8209 ‑; ‑ figure &#x2012; &#8210; &#x2012 &#8210 ‒; ‒ em &#x2013; &ndash; &#8211; &#x2013 &#8211 –; – en &#x2014; &mdash; &#8212; &#x2014 &#8212 —; — horbar &#x2015; &horbar; &#8213; &#x2015 &#8213 ―; ― minus &#x2212; &minus; &#8722; &#x2212 &#8722 −; − hybull &#x2043; &hybull; &#8259; &#x2043 &#8259 ⁃; ⁃ fe58 &#xfe58; &#65112; &#xfe58 &#65112 ﹘; ﹘ fe63 &#xfe63; &#65123; &#xfe63 &#65123 ﹣; ﹣ ff0d &#xff0d; &#65293; &#xff0d &#65293 －; － (?:([-‐‑‒–—―−⁃﹘﹣－])|(?:&(?:(?:#x(2d|201[0-5]|2212|2043|fe58|fe63|ff0d))|(?:#(45|820[89]|821[0123]|8722|8259|65112|65123|65293))|(hyphen|[nm]?dash|hybull|horbar|minus));?))` 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/