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

/
/
gms

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?ms)(?:(?:(\/)(\*)|(["'])).*?(?:\2\1|\3))|(?:\/\/[^\n]+)`) var str = ` //get means only read, but not to mutate data Get(BooksWithAuthors) //default queries via mycel .Query() //junction table to pair books and authors .From("BookAuthor".As(BA)) //main table for books .Join(left: Books.As(B) => B.Id == BA.BookId) //main table for authors .Join(left: Authors.As(A) => A.Id == BA.AuthorId) //groups by column, body allows to restore data (restructuring) .GroupBy(B.Id, => { B.Authors.Add(A) }) //ignore still registerd data objects for the response .SelectIgnore(BA) //or select only that fields or objects you want to response .Select(B) .Foo("//wrong-comment-inside-quotes") .Foo('//wrong-comment-inside-single-quotes') .Foo('some /*wrong-comment*/ inside') ; //get means only read, but not to mutate data Get(BooksWithAuthorsByMethod) //using individual backside methods (created by own) .GetBooksWithAuthors(id:6, filter:{key:'minAuthorAge', value:17}) ; /* comments "over" */ /* 'multiply lines' //with wrong comments inside *\ aa"aasdfasdasdf asdfasdfasdf asdfasdf"asdfasd ` 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/