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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"Json(?<json_output>[\s\S\d\D\w\W]*)", flags=re.MULTILINE) test_str = ("```json\n" "[\n" " {\n" " \"Place\": {\n" " \"Name\": \"Les Catacombes de Paris\",\n" " \"Google_place_id\": \"ChIJVXealLU_xkcRja_At0z9AGY\",\n" " \"City\": \"Paris\",\n" " \"Region\": \"Île-de-France\",\n" " \"Country\": \"France\",\n" " \"Cultural_type\": \"Historical\",\n" " \"Facts\": {\n" " \"Historical_facts\": {\n" " \"FACT_TYPE\": \"Did you know ?\",\n" " \"FACTS\": [\n" " \"Les Catacombes de Paris ont été créées à la fin du 18ème siècle pour résoudre le problème de surpeuplement des cimetières de la ville.\"\n" " ],\n" " \"INTERACTION\": [\n" " \"Savez-vous pourquoi les catacombes ont été construites ?\"\n" " ],\n" " \"CATEGORY\": \"Historical_facts\"\n" " },\n" " \"Architectural_facts\": {\n" " \"FACT_TYPE\": \"Fun fact\",\n" " \"FACTS\": [\n" " \"Les catacombes sont faites d’anciens tunnels de carrières transformés pour stocker les ossements de plus de six millions de Parisiens.\"\n" " ],\n" " \"INTERACTION\": [\n" " \"Combien de personnes pensez-vous que les catacombes peuvent contenir ?\"\n" " ],\n" " \"CATEGORY\": \"Architectural_facts\"\n" " },\n" " \"Scientific_facts\": {\n" " \"FACT_TYPE\": \"Wow\",\n" " \"FACTS\": [\n" " \"Les conditions dans les catacombes, qui sont fraîches et humides, permettent une bonne conservation des ossements.\"\n" " ],\n" " \"INTERACTION\": [\n" " \"Que pensez-vous que l'humidité fait aux ossements ?\"\n" " ],\n" " \"CATEGORY\": \"Scientific_facts\"\n" " },\n" " \"Mystery_legends_facts\": {\n" " \"FACT_TYPE\": \"Did you know ?\",\n" " \"FACTS\": [\n" " \"Une légende urbaine raconte qu’il y a un cinéma secret dans les catacombes !\",\n" " \"Il paraîtrait que des groupes se réunissent ici pour regarder des films.\"\n" " ],\n" " \"INTERACTION\": [\n" " \"Aimeriez-vous visiter un cinéma caché ?\",\n" " \"Quel genre de film pensez-vous qu’ils projettent là-bas ?\"\n" " ],\n" " \"CATEGORY\": \"Mystery_legends_facts\"\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