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

Code Generator

Language

Generated Code

import re regex = re.compile(r"(<([\w\:\-]+)(.+?)<\/\2>)") test_str = " <model name=\"user\" label=\"User / Device\"> <field name=\"device_label\" label=\"Device Label\" type=\"text:name\" /> <field name=\"logged_in_as_administrator\" label=\"Logged in as Administrator\" type=\"boolean\" /> <field name=\"logged_in_as_consultant\" label=\"Logged in as Consultant\" type=\"boolean\" /> <field name=\"logged_in_as_contractor\" label=\"Logged in as Contractor\" type=\"boolean\" /> <field name=\"logged_in_as_csd\" label=\"Logged in as CSD\" type=\"boolean\" /> <field name=\"logged_in_as_engineer\" label=\"Logged in as Engineer\" type=\"boolean\" /> <field name=\"logged_in_as_engineer_coordinator\" label=\"Logged in as Operations Coordinator\" type=\"boolean\" /> <field name=\"logged_in_as_procurement\" label=\"Logged in as Procurement\" type=\"boolean\" /> <field name=\"logged_in_as_sda\" label=\"Logged in as SDA\" type=\"boolean\" /> <field name=\"logged_in_as_pm\" label=\"Logged in as Project Manager\" type=\"boolean\" /> <field name=\"app_version\" label=\"App Version\" type=\"text\" /> <field name=\"updated_at\" label=\"Updated At\" type=\"text\" /> <belongs-to model=\"journey_account\" /> <belongs-to model=\"role\" name=\"current_role\" /> <has-many model=\"notification\" name=\"notifications\" /> <display>{device_label}</display> </model> " match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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