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"matei 200 inheritance", flags=re.MULTILINE) test_str = ("<?php\n\n" "class Device {\n" " protected $name;\n" " protected $isOn = false;\n" " \n" " function __construct($name = \"Unknown Device\") {\n" " $this->name = $name;\n" " }\n" " \n" " function turnOn() {\n" " $this->isOn = true;\n" " echo \"{$this->name} is turned on.<br>\";\n" " }\n" " \n" " function turnOff() {\n" " $this->isOn = false;\n" " echo \"{$this->name} is turned off.<br>\";\n" " }\n" " \n" " function getStatus() {\n" " $status = $this->isOn ? \"on\" : \"off\";\n" " echo \"{$this->name} is currently {$status}.<br>\";\n" " }\n" "}\n\n" "class Smartphone extends Device {\n" " private $photos = 0;\n" " \n" " function __construct($name = \"Smartphone\") {\n" " parent::__construct($name);\n" " }\n" " \n" " function takePhoto() {\n" " if ($this->isOn) {\n" " $this->photos++;\n" " echo \"Photo taken! (Total: {$this->photos} photos)<br>\";\n" " } else {\n" " echo \"Please turn on the {$this->name} first!<br>\";\n" " }\n" " }\n" " \n" " function showPhotoCount() {\n" " echo \"Number of photos: {$this->photos}<br>\";\n" " }\n" "}\n\n\n" "echo \"<h3>Device Class:</h3>\";\n" "$myDevice = new Device(\"Television\");\n" "$myDevice->turnOn();\n" "$myDevice->getStatus();\n" "$myDevice->turnOff();\n" "$myDevice->getStatus();\n\n" "echo \"<br><h3>Smartphone Class:</h3>\";\n" "$myPhone = new Smartphone(\"iPhone 15\");\n" "$myPhone->getStatus();\n" "$myPhone->takePhoto();\n" "$myPhone->turnOn();\n" "$myPhone->takePhoto();\n" "$myPhone->takePhoto();\n" "$myPhone->takePhoto();\n" "$myPhone->showPhotoCount();\n" "$myPhone->turnOff();\n" "?>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} 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