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)<(?<root>[A-Z_]+)(?: .*?>|>).*?<\/\k<root>>`) var str = `<?xml version="1.0" encoding="windows-1251" ?><ELEM_LIST><ELEM PLAYER_NAME="Плеер" STATUS="playing"><START_TIME>15:49:41</START_TIME><BLK_TYPE>М</BLK_TYPE><TYPE>М</TYPE><NAME>Heathens</NAME><ARTIST>Twenty One Pilots</ARTIST><AUTHOR></AUTHOR><ALBUM></ALBUM><DBID></DBID><FILE_NAME>H:\Radio\Music\Twenty One Pilots - Heathens.mp3</FILE_NAME><DURATION>00:03:10</DURATION></ELEM><ELEM PLAYER_NAME="Плеер" STATUS="preloaded"><START_TIME></START_TIME><BLK_TYPE>М</BLK_TYPE><TYPE>Д</TYPE><NAME>ID #5</NAME><ARTIST>Jingle</ARTIST><AUTHOR></AUTHOR><ALBUM></ALBUM><DBID></DBID><FILE_NAME>H:\Radio\Jingle's\ID #5.mp3</FILE_NAME><DURATION>00:00:01</DURATION></ELEM></ELEM_LIST>` 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/