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"@param\s+\{\(?([^}]+)\)?\}\s+(\[.+\]|[\w]+(?:\[.+\])?)\s+([\s\S]*?)(?=\@|\*\/)", flags=re.IGNORECASE | re.MULTILINE) test_str = ("/**\n" " * Removes elements from \\`array\\` corresponding to \\`indexes\\` and returns an\n" " * array of removed elements.\n" " *\n" " * **Note:** Unlike \\`_.at\\`, this method mutates \\`array\\`.\n" " *\n" " * @static\n" " * @memberOf _\n" " * @category Array\n" " * @param {Array} array The array to modify.\n" " * @param {...(number|number[])} [indexes] The indexes of elements to remove,\n" " * specified individually or in arrays.\n" " * @returns {Array} Returns the new array of removed elements.\n" " * @example\n" " *\n" " * var array = [5, 10, 15, 20];\n" " * var evens = _.pullAt(array, 1, 3);\n" " *\n" " * console.log(array);\n" " * // => [5, 15]\n" " *\n" " * console.log(evens);\n" " * // => [10, 20]\n" " */\n" "var pullAt = rest(function(array, indexes) {\n" " indexes = arrayMap(baseFlatten(indexes), String);\n\n" " var result = baseAt(array, indexes);\n" " basePullAt(array, indexes.sort(compareAscending));\n" " return result;\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