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

r"
"
gmu

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)([0-9]{1,2}:[0-9]{2}) (AM|PM)(\n)(.*)\n`) var str = `5:47 PM [EASY] Panzer Pebble joined the server 5:47 PM Trigger executed raw command message "76561199679367168" Welcome to EASY Company | Level 50+! If you have any issues, please report it by typing !admin (reason) in chat. Come check us out at discord.gg/easycompany. You MUST be level 50 or higher to play on this server and level 75 or higher to play commander. 5:47 PM Player [EASY] Panzer Pebble switched from None to Allies 5:47 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [We are trying to populate the server which means special rules apply. 5:56 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [Vote for the nextmap: 5:59 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [We are trying to populate the server which means special rules apply. 5:59 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [This server is under level thresholds control. 6:18 PM Player [EASY] Panzer Pebble switched from None to Axis 7:28 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [Vote for the nextmap: 7:48 PM MASTER CHIEF (Axis) killed [EASY] Panzer Pebble (Allies) with GEWEHR 43 7:49 PM Yustitsiya (Axis) killed [EASY] Panzer Pebble (Allies) with MP40 9:00 PM MESSAGE: player [[EASY] Panzer Pebble(76561199679367168)], content [Vote for the nextmap:` var substitution = "\g<1>\g<2> \g<4>\n" 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/