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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
gim

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?im)'\$([\d]*)[\.]?(\d+)'`) var str = `#Test-2019-8 #1.'do+g' dog, doooog, abcdogef, asdooooijk dooog asdoogghj 'dog', 'doooog', 'abcdogef' #2. 'ab*d' ad, abd, abbbd 'ad', 'abd', 'abbbbd' 'sad', 'cabd', 'abbbds' #3. '[xy]{2}AB' 'xxAB', 'xyAB','yyAB' '2xxAB' #4. '[a-z].?' 'aA', 'b9', 'z' 'bX' 'aB z8 b6' #5. '5[abc]?ef' '5aef', 'a5bef', '5ef' '5ef' #6. Taiwan ID : '([A-Z])([12])(\d{8})','[A-Z][12]\d{8}' 'A102926987', 'B212345678' #7. mobile tel_num:'(09)(\d\d)[-\s](\d{3})[-\s](\d{3})' '0988 123 456', '0978-456-789' # : '09\d\d[-\s]\d\d\d' '0924-357' #8. Home tel_num: # '([\(]?\d\d[\)-]?)([\d]{4})([-\s]{1}[\d]{4})' '(02)2257 3150', '02-2250-3457','(12)2245 3214' # '[\(]?(0[23])[\)-]?(\d{4})' '(02)2345', '03-1348' #9. Date Time:yyyy/mm/dd #'(20[12]\d)[-\/]([1]?[\d])[-\/]([1-3][\d])' '2019/1/25', '2018-12-31' #'(20[12]\d)[-\/]([01]\d)[-\/](\d{2})' '2019/01/15' ,'2020-11-28' #10. floating number: '\$([\d]*)[\.]?(\d+)' '$123.34', '$2345' '$0.234' ,'1.87' ` 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/