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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(\[)(\d+)(\].*')(.+)(')`) var str = ` [1] = 0 'NumProgPlc' [2] = 3 'PadCode' [3] = 2 'TablePos' [4] = 1 'CurrentTool' [5] = 0 'Loc. Override' [10] = .200000 'PlaceDelay' [11] = .300000 'PickDelay' [12] = .150000 'ChamfersChkDelay' [15] = -107.575500 'xLpos' [16] = 398.586304 'yLpos' [17] = 277.373779 'zLpos' [18] = 90.000000 'RotApproNasAlim' [21] = 53 'PR Offset Tavola' [22] = 110 'PR Sopra Tavola' [23] = 267 'DO Magnete ON' [24] = 268 'DO Magnete OFF' [25] = 243 'DI PresPastTav' [26] = 247 'DI PezNoPrelTav' [27] = 1 'DO Soffio' [28] = 111 'PR Tavola+20' [29] = 112 'PR Tavola' [30] = 0 '_Prelevato' [31] = 0 '_ScartoTav' [32] = 0 '_ScartoCtrlUs' [33] = 0 '_ScambioTav' [34] = 0 '_CaricoTav' [35] = 1 'FlagMemPtoNasAli' [36] = 244 'DO PezPrelTav' [37] = 243 'DO PezScamTav' [38] = 242 'DO PezDepoTav' [39] = 132 'PR Tavola+50' [45] = 229 'DI PezPrelNas' [46] = 1 'OK_PRL' [50] = 1 'PrioritaNas' [51] = 0 'CaricoNas' [55] = 0 'Conveyor2Rot180' [200] = 3.216000 'TC' ` var substitution = "R\t\2\t\4" fmt.Println(re.ReplaceAllString(str, substitution)) }

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/