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

/
/
g

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(biovar)? *(?P<number>\d+)?[, ]*(?P<addition>\w+)?`) var str = `biovar 1 ? biovar 1 biovar 1 biovar 1 biovar 3 1 1 1 1 1 1 1 1 ? ? ? ? ? ? 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 3 3 6 7 1 1 1 3 3 6 3 ? 1 1 4 2 1 1 1 1 3 3 3 1 1 9 ? 6 6 1 2 1 1 ? 3 1 1 3 1 2 1 1 1 3 3 3 ? 2 2 ? ? ? ? ? ? 2 9 ? ? 4 3 5 5 ? 1 9 6 2 ? 6 3 1 1 ? 3 ? 1 3 2 ? 1 1 1 ? ? ? ? ? ? 2 ? ? ? ? ? 2 ? ? ? biovar 1 ? biovar 1 biovar 1 biovar 1a biovar 1 biovar 1a ? ? ? biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 2 ? ? ? 6 6 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? biovar 3 biovar 1 biovar 1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 4 ? 1 1 2, atypical 1 1 1 1 1 1 1, atypical 4 2 2 1 1 1 1 1 1 1 3b 4 2 7 7 6 9 7 7 ? ? 1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? biovar 1 biovar 1 biovar 1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? biovar 1 ? ? ? ? ? ? ? ? ? ? ? ? biovar 3 ? ? ? ? ? ? ? biovar 3 biovar 3 biovar 1 biovar 1 biovar 1 biovar 3 ? ? ? ? ? ? ? ? ? ? biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 ? biovar Abortus ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? biovar 2 ? biovar 3 biovar 4 ? biovar 5 biovar 6 ? biovar 9 ? ? ? ? ? ? ? ? ? ? ? ? ? biovar 1 biovar 2 ? biovar 3 ? biovar 3 ? biovar 4 ? biovar 5 ? ? ? ? biovar I biovar 2 biovar 2 biovar 2 biovar 2 biovar 2 biovar 2 biovar 2 biovar 4 biovar 4 biovar 4 biovar 4 biovar 4 biovar 4 biovar 4 biovar 4 biovar 4 biovar 3 biovar 1 biovar 1 biovar 1 biovar 1 biovar 1 biovar 2 biovar 2 biovar 2 biovar 2 biovar 2 ? ? ? ? ?` 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/