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)^(.*ViPNet CSP( \(версия)? 4\.2\)?|\"Крип(р|т)оПро CSP\" \(?версия (4\.0|3\.9)\)?|Криптотокен (2 )?ЭП.*|Рутокен ЭЦП.*)`) var str = `"КрипроПро CSP" (версия 4.0) "КриптоПро CSP" (версия 3.6) "КриптоПро CSP" (версия 3.9) "КриптоПро CSP" (версия 4.0) "КриптоПро CSP" версия 3.6 "КриптоПро CSP" версия 3.9 "КриптоПро CSP" версия 4.0 Crypto-Pro GOST R 34.10-2001 Cryptographic Service Provider 3.9 Crypto-Pro GOST R 34.10-2001 Cryptographic Service Provider 4.0 JCrypto SDK 2.7.3-R321 ViPNet CSP (версия 3.2) ViPNet CSP (версия 4.2) ViPNet CSP 4.0 ViPNet CSP 4.1 ViPNet CSP 4.2 Криптотокен ЭП (0c53000205156035) Рутокен ЭЦП 2.0 (0c53000216296035) Криптотокен 2 ЭП (0c53002119206034) Криптотокен ЭП (4e3900052631304c) Криптотокен ЭП (4e46001821075047) Рутокен ЭЦП (4e46001839795047) Криптотокен ЭП (4e46001951815047) СКЗИ «Криптотокен» в составе изделия «JaCarta ГОСТ» Средство криптографической защиты информации (СКЗИ) ViPNet CSP 4.2 Средство криптографической защиты информации ViPNet CSP 4.2 ` 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/