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

/
/
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)\b(\d+\/\d+\/\d+)\b`) var str = `0 03/25/93 Total time of visit (in minutes):\n 1 6/18/85 Primary Care Doctor:\n 2 sshe plans to move as of 7/8/71 In-Home Servic... 3 7 on 9/27/75 Audit C Score Current:\n 4 2/6/96 sleep studyPain Treatment Pain Level (N... 5 .Per 7/06/79 Movement D/O note:\n 6 4, 5/18/78 Patient's thoughts about current su... 7 10/24/89 CPT Code: 90801 - Psychiatric Diagnos... 8 3/7/86 SOS-10 Total Score:\n 9 (4/10/71)Score-1Audit C Score Current:\n 10 (5/11/85) Crt-1.96, BUN-26; AST/ALT-16/22; WBC... 11 4/09/75 SOS-10 Total Score:\n 12 8/01/98 Communication with referring physician... 13 1/26/72 Communication with referring physician... 14 5/24/1990 CPT Code: 90792: With medical servic... 15 1/25/2011 CPT Code: 90792: With medical servic... 16 4/12/82 Total time of visit (in minutes):\n 17 1; 10/13/1976 Audit C Score, Highest/Date:\n` 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/