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

/
/
gmx

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?>->)(?<method>\w+)\s*\( (?> (?> (?> (?> (?<parameter1>(?>(?>'\d{1,2}:\d{1,2}')|(?>'[*\s]+'))|(?>'?\d+'?))? (\s*,\s*(?<parameter2>(?>(?>'\d{1,2}:\d{1,2}')|(?>'[*\s]+'))|(?>'?\d+'?)))? (\s*,\s*(?<parameter3>(?>(?>'\d{1,2}:\d{1,2}')|(?>'[*\s]+'))|(?>'?\d+'?)))? ) ) )? )? \)`) var str = `->dailyAt('13:00') ->cron('* * * * *') ->everyMinute(1) ->everyTwoMinutes() ->everyThreeMinutes() ->everyFourMinutes() ->everyFiveMinutes() ->everyTenMinutes() ->everyFifteenMinutes() ->everyThirtyMinutes() ->hourly() ->hourlyAt(17) ->everyTwoHours() ->everyThreeHours() ->everyFourHours() ->everySixHours() ->daily() ->dailyAt('13:00') ->twiceDaily(1, 13) ->weekly() ->weeklyOn(1, '8:00') ->monthly() ->monthlyOn(4, '15:00') ->twiceMonthly(1, 16, '13:00') ->twiceMonthly('1', '16', '13:00') ->lastDayOfMonth('15:00') ->quarterly() ->yearly() ->yearlyOn(6, 1, '17:00') ->timezone('America/New_York')` 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/