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(`(\S| )+\n(\S| )+\n(\S| )+\n((\S| )+|)NSW \d{4}`) var str = `/////// 4 lines & 3rd line is suburb only SCIENTIFIC MOTOR BODYWORKS LP 7-9 PERRY STREET MATRAVILLE NSW 2036 /////// au Mascot Auto Repairs"cod** 155 Coward Street Mascot NSW 2020 //////////////////////// Mascot Airport Service Station *cod* Inside Car Wash 237 O'Riordan St Mascot NSW 2020 ////////////////////////maps 7/30-32 Beaconsfield Street Alexandria NSW 2015 //////////////////////// Pedders Mascot Unit 1 20 Ricketty Street Mascot NSW 2020 ///////////////////// Pay Charge Mr Bump Smash Repair Unit 12/122 Station Rd Seven Hills NSW 2147 //////////////////// Pay Charge Mr Bump Smash Repair Unit 12 122 Station Rd Seven Hills NSW 2147 /////// suburb spelling error, character in street line Woollahra Auto***cod*** 120, Oxford St Woolahra NSW 1350 /// name not complete North Caringbah Smash Rep 47 Captain Cook Drive Caringbah NSW 2229 ///// BM Pro Service Centre Unit8/ 1a Pritchard Plac Peakhurst NSW 2210 //// embassy smash repairs unit 5d 23-25 windsor rd northmead nsw 2152` 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/