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"
"
gm

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?:\d{1,3})\s+(?:Platform Alarm\(\d+\))\s+\d+\s+(\d+).+(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}).+nodeBId:(\d+).+Office Name\(Site\)=([\w_]+)`) var str = `277 Platform Alarm(20420) 1337 198092557 User-defined dry contact alarm 8 Minor SubNetwork=75,MEID=5721,Equipment=1,Rack=1,SubRack=1,Slot=13 2021-06-21 04:27:39 U RNCId: 75; Dry contact ID: 6; Board serial number: 274808900275; U nodeBId:5721 Office ID(Site)=5721/Office Name(Site)=San_Telmo/Alarm Object Type=SDR/Alarm Object ID=5721/Alarm Object Name=San_Telmo/Board Type=SA 75-5721-1_1_13_1_198092557_6 12 Radio Controller(1701) 100001 41591 1615258887314 Processing Alarm 83886256 NodeB is out of service Critical SubNet(75)/ManagedElement(75)/Rack No.(1)/Shelf No.(1)/Board No.(8)/CPU No.(1) 2021-03-29 20:08:33 Alarm Object:NODEB; \nNodeB ID:5433; \nAlarm sub code:2; \nIub Transport bearer type:IP V4 Bearer Type; \nLink Number:1; \nLink ID list:1126;\nLogic Position:System No.:0,Module No.:7,Index:0; RNCSCB04 83886768 NCP link failure Office ID(Site)=5433/Office Name(Site)=Tariba/Alarm Object Type=NODEB/Alarm Object ID=5433/Alarm Object Name=Tariba/Board Type=CDR/APP Type=product:wcdma,wcdma/Object MOC=UIUBLINK/Object DN=SubNetwork=75,MEID=75,URncFunction=75,UIubLink=5433 ` 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/