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"(?|([a-zA-Z0-9]+)[({[«]([a-zA-Z\s]+)[)}\]»]|[({[«]([a-zA-Z\s]+)[)}\]»]([a-zA-Z0-9]+))") test_str = ("// i want to mark for single brackets examples below other heighlight pattren not disturb.please\n" "(weather // i want to mark this word\n" "weather) // i want to mark this word\n" "(weather is good // i want to mark this word\n" "weather is good) // i want to mark this word\n" "weathe)r\n" "wea(ther\n" "and same for other brackets {,[,«\n" "{weather // i want to mark this word\n" "weather} // i want to mark this word\n" "{weather is good // i want to mark this word\n" "weather is good} // i want to mark this word\n" "weathe}r // i want to mark this word\n" "weathe{r // i want to mark this word\n\n" "[weather // i want to mark this word\n" "weather] // i want to mark this word\n" "[weather is good // i want to mark this word\n" "weather is good] // i want to mark this word\n" "weathe]r // i want to mark this word\n" "weathe[r // i want to mark this word\n" "«weather // i want to mark this word\n" "weather} // i want to mark this word\n" "«weather is good // i want to mark this word\n" "weather is good» // i want to mark this word\n" "weathe»r // i want to mark this word\n" "weathe»r // i want to mark this word\n\n" "(Weather) is good. // not need to mark this beacuase this word correct word\n" "Weath(er) is good. // mark\n" "Weath(er is good). // mark\n" "Weather (is) (good).\n" "My name is Rah(eel) // mark\n" "Best pro(duct) // mark\n" "(Weather is good) // not need to mark this beacuase this word konown word\n" "we(ather)\n" "(weath)er is good. // mark\n" "(weath)er // mark\n" "weather(is fine)\n" "weather is good\n" "{weather is good} //not need to mark correct\n" "weat{er is good} // mark\n" "we{ather} is fine // mark\n\n" "{weathe}r is fine // i want to mark this word\n" "{weather is fin}e // i want to mark this word\n\n" "[weather is good] //not need to mark correct\n" "weat[her is good] // mark\n" "we[ather] is fine // mark\n\n" "[weathe]r is fine // mark\n" "[weather is f]ine // mark\n\n" "we[ather] is fine // mark\n\n" "«weather is good» //not need to mark\n" "weat«her is good» // mark\n\n" "we«ather» is fine // mark\n\n" "«weat»her is fine // mark\n" "«weather is fi»ne // mark\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