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
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

$re = '/LOG FORMAT.*\[(.*)\].*#/m'; $str = '#KEEP THIS FILE IN THE SAME DIRECTORY AS __INIT.PY__, OTHERWISE IT WON\'T WORK SETTINGS: FILE TO BE SORTED: "C:\\Temp\\xmls - Copy" #IF YOU ENTER "in" HERE THEN YOU CAN ENTER FILENAME FROM THE CONSOLE MINIMUM DISPLAY LEVEL OF LOGS: 10 #Warning = 30, Info = 20, Debug = 10, Notset = 0 LOG DELIMITER SYMBOL: "dupa" #A SYMBOL WHICH SEPARATES THE LOG FORMAT MODULES FILE TO STORE LOGS: "DEFAULT" #TO CHANGE IT, PASTE FULL PATH OF THE CHOSEN DIRECTORY, RMEMBER TO PUT NAME.TXT AT THE END. DEFAULT = directory of __init.py__ LOG FORMAT: [LEVELNAME, ASCTIME, MESSAGE] #A FORMAT IN WHICH LOGS WILL BE STORED IN THE FILE (Surrounded by [] brackets) *** LIST OF ATTRIBUTES: LEVELNAME, #Text logging level for the message (\'DEBUG\', \'INFO\', \'WARNING\', \'ERROR\', \'CRITICAL\'). ASCTIME, #Human-readable time when the LogRecord was created. By default this is of the form ‘2003-07-08 16:49:45,896’ (the numbers after the comma are millisecond portion of the time). MESSAGE, #The logged message, computed as msg % args. FUNCNAME, #Name of function containing the logging call. FILENAME, #Filename portion of pathname. PATHNAME, #Full pathname of the source file where the logging call was issued (if available). EMPTY #log will not be stored (IT SHOULD BE THE ONLY ONE MODULE IN THE LOG FORMAT) ADDITIONAL ATTRIBUTES: CREATED #Time when the LogRecord was created (as returned by time.time()). LEVELNO #Numeric logging level for the message (DEBUG, INFO, WARNING, ERROR, CRITICAL). LINENO #Source line number where the logging call was issued (if available). MODULE #Module (name portion of filename). MSECS #Millisecond portion of the time when the LogRecord was created. NAME #Name of the logger used to log the call. PROCESS #Process ID (if available). PROCESSNAME #Process name (if available). RELATIVECREATED #Time in milliseconds when the LogRecord was created, relative to the time the logging module was loaded. THREAD #Thread ID (NOT available) THREADNAME #Thread name (NOT available). *** '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php