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

/
/
gmi

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mi)^([a-z0-9_-]+)(\.[a-z0-9_-]+)?@([a-z0-9_-]+)\.([a-z0-9]{2,})$`) var str = `<header class="noSelect"> <div id="HIAccueil" class="I-B"> <img class="pointer" src="IMG/BACKGROUND/HEADER/logoban.png" alt="Accueil" onclick="clickMenu(tousLesMenus, 2, tousLesMenus[0].nom, 1, 0, 0, 0, tousLesMenus[1].url);"> </div> <div id="HIPC"> <div id="HIProfile" class="I-B"> <!-- vide pour img via js --> </div> <div id="HIConnect" class="I-B"> <img class="pointer" src="IMG/BACKGROUND/HEADER/connect_hover.gif" alt="Connect" onclick="clickMenu(tousLesMenus, 5, tousLesMenus[0].nom, 4, 1, 1, 0, tousLesMenus[4].url);"> </div> </div> </header> Tralloc_Nivek-02.baza_R-d421@gmail45.com Tralloc_Nivek-02@gmail45.com Tralloc_Nivek-02.baza_R-d421gmail45.c 010/226679 010226679 010/22.66.79 010/22 66 79 0470040747 0470/040747 0470/040.747 0470/04.07.47 0470/04 07 47 0470/040 747 +0032470040747 0032470/040 747 +00320470040747` 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/