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

/
/
mg

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)((\d|:)+)\s(.+)`) var str = `0:08 Waltz No. 2 (Dmitri Shostakovitch) 4:01 Dance of the Knights (Sergei Prokofiev) 9:42 Sabre Dance (Aram Khachaturian) 12:09 1812 Overture Finale (Pyotr Ilyich Tchaikovsky) (My Absolute Favorite One) 15:57 Flight of the Bumblebee "From The Tale of Tsar Sultan" (Nikolai Rimsky-Korsakov) 19:31 Rite of Spring Sacrifical Dance (Igor Stravinsky) 24:09 Piano Concerto No. 2 (Moderato) (Sergei Rachmaninoff) 34:22 Polovtsian Dances "From Prince Igor" (Alexander Borodin) 39:20 Etude Op. 8 No. 12 (Alexander Scriabin) 41:51 Sailors' Dance (Reinhold Gliere) 45:13 Dance of the Sugar Plum Fairy (Pyotr Ilylich Tchaikovsky) 47:46 Piano Concerto No. 1 (Allegro) (Pyotr Ilylich Tchaikovsky) 51:54 Ruslan and Lyudmila Overture (Mikhail Glinka) 54:51 Swan Lake Waltz (Pyotr Ilyich Tchaikovsky) 1:01:47 Dance of the Pagan Monster (Sergei Prokofiev) 1:05:01 Overture from the Children of Captain Grant (Isaak Dunaevsky) 1:08:52 Symphony No. 5 (Allegro Non Troppo) (Dmitri Shostakovitch) (My Favorite One) 1:12:00 Swan Theme (Pyotr Ilyich Tchaikovsky) 1:14:53 Night on Bald Mountain (Modest Mussorgsky)` 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/