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
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r"\[([^]]*)\]", flags=re.MULTILINE) test_str = ("[EtlRowId]\n" " ,[PartitionKey]\n" " ,[RowKey]\n" " ,[Timestamp]\n" " ,[LoadDTS]\n" " ,[Microsoft_VSTS_Common_BacklogPriority]\n" " ,[Microsoft_VSTS_Common_Priority]\n" " ,[Microsoft_VSTS_Common_ValueArea]\n" " ,[Microsoft_VSTS_Scheduling_Effort]\n" " ,[System_AreaPath]\n" " ,[System_BoardColumn]\n" " ,[System_BoardColumnDone]\n" " ,[System_ChangedBy]\n" " ,[System_ChangedDate]\n" " ,[System_CommentCount]\n" " ,[System_CreatedBy]\n" " ,[System_CreatedDate]\n" " ,[System_IterationPath]\n" " ,[System_Reason]\n" " ,[System_State]\n" " ,[System_Tags]\n" " ,[System_TeamProject]\n" " ,[System_Title]\n" " ,[System_WorkItemType]\n" " ,[TeamNowCustomerId]\n" " ,[fields]\n" " ,[id]\n" " ,[projectId]\n" " ,[projectName]\n" " ,[rev]\n" " ,[url]\n" " ,[Microsoft_VSTS_Common_ClosedDate]\n" " ,[System_AssignedTo]\n" " ,[BugIterationHash]\n" " ,[TeamIterationHash]\n" " ,[BugHash]") subst = "MAX(LEN([${1}])) AS [${1}]" result = regex.sub(subst, test_str) if result: print(result)

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 Python, please visit: https://docs.python.org/3/library/re.html