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

/
/
i

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?i)Aankomst:\sMAANDAG\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|dinsdag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|woensdag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|donderdag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|vrijdag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|zaterdag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:|zondag\s([0-9][0-9]\/[0-9][0-9]\/[0-9][0-9][0-9][0-9])\s\s\s\sVertrek:`) var str = ` +++++++++++++++++++++++++++++++++++++++++++++++ + Ref Document: 137165 + +++++++++++++++++++++++++++++++++++++++++++++++ From: jamirequest@jetair.be emaildestin;L ;137165;yourname jetair@groupepvcp.com CENTER PARCS ERPERHEIDE Uw code: 78154 / BLI Datum: 18/11/15 ***** Reservering in allotment ***** Reserveringsnummer: 021146151 SJ Reserveringsdatum: 18/11/2015 Gelieve de volgende reservering te noteren aub aan contractprijs Aankomst: zondag 01/02/2016 Vertrek: vrijdag 05/02/2016 4 Nachten. 1 x type 30: EP082 app. 2 pers. comfort Bad of douche, Terras, TV, Kitchenette In allotment Logies MIDWEEKVERBLIJF 01/02/16 - 05/02/16 EARLY BOOKING Mr. D.DEBERGH 28 jaar Mevr. S.BOUDEN 25 jaar Het is niet nodig deze reservering te herbevestigen Opmerkingen/speciale wensen indien mogelijk babybed cpref,021146151,... Einde van het bericht` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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/