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

/
/
gx

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`editor\s*\{[^{}"]* # Notice that I enabled the /x flag -----> # That just allows me to add comments here to make it more readable # Match from opening to closing double quote for the 'key' "[^"]*" # Then any whitespace between the 'key' and 'value' \s+ # Match from opening to closing double quote for the 'value' "[^"]*"`) var str = `"entity" { "id" "5040044" "classname" "weapon_defibrillator_spawn" "angles" "0 0 0" "body" "0" "disableshadows" "0" "skin" "0" "solid" "6" "spawnflags" "3" "origin" "449.47 5797.25 2856" editor { "color" "0 0 200" "visgroupshown" "1" "visgroupautoshown" "1" "logicalpos" "[-13268 14500]" } editor { "color" "0 0 200" "visgroupshown" "1" "visgroupautoshown" "1" "logicalpos" "[-13268 14500]" "specialchars" "}" } editor { "child" "0 0 200" "visgroupshown" "1" "visgroupautoshown" "1" "logicalpos" "[-13268 14500]" subgroup { "child" "42 42 42" } } } ` 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/