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

/
/
gis

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"<(?:textarea|select).*?>.*?(\{\{\{variable:(.*?)\}\}\}).*?<\/(?:textarea|select)>|<(?:input).+?(value=.*?)(\{\{\{variable:(.+?)\}\}\})?.*?>|(\{\{\{variable:(.*?)\}\}\})" test_str = (" <section id=\"services\">\n" " <div class=\"container\">\n" " <div class=\"row\">\n" " <div class=\"col-md-12\">\n" " <p>You are using system version: {{{variable:system_version}}}</p>\n" " <p>Your address: {{{variable:contact-email-address}}}</p>\n" " <form action=\"http://k.loc/content/view/welcome\" class=\"default-form\" enctype=\"multipart/form-data\" method=\"post\" accept-charset=\"utf-8\">\n" " <input type=\"hidden\" name=\"csrfkcmstoken\" value=\"94ee71ada809b9a79d1b723c81020c78\" />\n\n" " <div class=\"row\">\n" " <div class=\"col-sm-12 form-error\"></div>\n" " </div>\n" " <div class=\"row\"><div class=\"col-sm-12\"><fieldset id=\"personalinfo\"><legend>Personal information</legend><div class=\"row\"><div class=\"col-sm-12\">\n" " <div class=\"control-label\">\n" " <label for=\"testinput\">Name<span class=\"form-validation-required\"> * </span></label>\n\n" " </div>\n" " <div class=\"hint-text\">Enter at least 2 characters and a maximum of 12 characters.</div><input id=\"testinput\" name=\"testinput\" placeholder=\"Enter your name here.\" class=\"input-group width-50\" type=\"text\" value=\"{{{variable:system_name}}} {{{variable:system_login}}}\"><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div><div class=\"row\"><div class=\"col-sm-12\">\n" " <div class=\"control-label\">\n" " <label for=\"testpassword\">Password</label>\n\n" " </div>\n" " <div class=\"hint-text\">Your password must be at least 12 characters long, contain 1 special character, 1 nunber, 1 lower case character and 1 upper case character.</div><input id=\"testpassword\" name=\"testpassword\" placeholder=\"Enter your password here.\" class=\"input-group width-50\" type=\"password\"><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div></fieldset></div></div><div class=\"row\"><div class=\"col-sm-12\"><fieldset id=\"bioinfo\"><legend>Biographical information</legend><div class=\"row\"><div class=\"col-sm-12\">\n" " <div class=\"control-label\">\n" " <label for=\"testtextarea\">Biography</label>\n" " <span class=\"hint-text\">A minimum of 40 characters and a maximum of 255 is allowed. This hint is displayed inline.</span>\n" " </div>\n" " <textarea id=\"testtextarea\" name=\"testtextarea\" placeholder=\"Please enter your biography here.\" class=\"input-group-wide width-100\" rows=\"5\" cols=\"80\">{{{variable:system_name}}}\n\n" "{{{variable:system_login}}}</textarea><div class=\"row\"><div class=\"col-sm-12\"><div class=\"form-error\"></div></div></div></div></div><div class=\"row\"><div class=\"col-sm-12\">\n" " <div class=\"control-label\">\n" " <label for=\"testsummernote\">Interests</label>\n" " <span class=\"hint-text\">A minimum of 40 characters is required. This hint is displayed inline.</span>\n" " </div>\n" " <textarea id=\"testsummernote\" name=\"testsummernote\" class=\"wysiwyg-editor\" placeholder=\"Please enter your interests here.\"><p>{{{variable:system_name}}}<br></p><p>{{{variable:system_login}}}</p><p>{{{variable:activate_url}}}<br></p></textarea></div></div></fieldset></div></div><div class=\"row\"><div class=\"col-sm-12\"><button name=\"testsubmit\" id=\"testsubmit\" type=\"submit\" class=\"btn primary\">Submit<i class=\"zmdi zmdi-arrow-forward\"></i></button></div></div>\n" " </form> </div>\n") matches = re.finditer(regex, test_str, re.IGNORECASE | re.DOTALL) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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