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".*@(\S+)") test_str = ("From: <email@example.com> FROM name fails\n\n" "Closed (fixed)\n" "Project: \n" "SMTP Authentication Support\n" "Version: \n" "6.x-1.0-beta5\n" "Component: \n" "Code\n" "Priority: \n" "Normal\n" "Category: \n" "Bug report\n" "Assigned: \n" "José San Martin\n" "Reporter: \n" "goose2000\n" "Created: \n" "July 8, 2008 - 12:54\n" "Updated: \n" "October 5, 2012 - 19:01\n" "Log in or register to update this issue\n" "Jump to:\n" "Most recent attachment\n" "Hi, my development site is running on IIS with SMTP server. Mail is working fine when creating new users or getting a password reset. I have built a webform and upon submitting I'll get this error:\n\n\n" " * warning: mail() [function.mail]: SMTP server response: 501 5.5.4 Invalid Address in C:\\Inetpub\\wwwroot\\BHI_dev\\includes\\mail.inc on line 193.\n" " * Unable to send e-mail. Please contact the site admin, if the problem persists.\n\n" "The address I use in my testing are in fact completely valid. Seems like webform is not playing nice with the core somehow. Further ideas?\n\n" "Using Drupal 6.2.\n\n" "Thanks.\n\n" "Files: \n" "Comment File Size Author\n" "#25 smtp_279836.patch 694 bytes scttnlsn\n" "#13 smtp_module_name_patch_279836_01.patch 724 bytes franz\n" "#6 smtp_module_name_patch_279836_01.patch 724 bytes rfay\n" "Comments\n" " goose2000’s picture\n" "Comment #1goose2000 CreditAttribution: goose2000 commented 8 years ago\n" "Priority: Critical » Minor\n" "This seems to be an IIS SMTP issue only. See here:\n\n" "http://drupal.org/node/33967\n\n" "Easy work around is to have no 'name' text , just the email address when you configure webform.\n" "Think it may still be fixable at the code? I set it to 'minor' now.\n\n" "Working great, one of the best modules around.\n" "Log in or register to post comments\n" " quicksketch’s picture\n" "Comment #2quicksketch CreditAttribution: quicksketch commented 7 years ago\n" "Title: Email Invalid Address » \"Name\" <email@example.com> FROM name fails\n" "Project: Webform » SMTP Authentication Support\n" "Version: 6.x-2.1.1 » 6.x-1.0-beta3\n" "Moving to the SMTP module.\n\n" "To summarize, Webform users have not been able to send e-mails when using the SMTP module and the FROM e-mail addresses are formatted as \"First Last\" <email@example.com>. The name is properly mime_header_encoded when necessary.\n\n" "Any users experiencing this issue, please update with the version of SMTP module you're using.") 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