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

/
/
i

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"([\s\S]*?)[\s]*def (\w+)Impl\((.*)\):[\s]+\"\"\"[\s]+([\s\S]*?)[\s]+\"\"\"([\s\S]*?)((def|$)[\s\S]*)$" test_str = ("def TestUnParamImpl(param1):\n" " \"\"\"\n" " @param param1 string Param named param1\n" " @return return1 string Return named return1\n" " \"\"\"\n" " \n" " \"\"\"\n" " # Imported code :\n" " \n" " import json\n" " d = json.loads(jsonstr)\n\n" " # To use the input params, simply use d[\"param1\"] \n" " # Your code here\n\n" " ret_dict = {}\n" " ret_dict[\"return1\"] = \"\"\n" " return json.dumps(ret_dict)\n" " \"\"\"\n" " \n" " return {\n" " \"return1\": \"string\"\n" " }\n\n" "def TestDeuxParamsImpl(paramString, paramInt):\n" " \"\"\"\n" " @param paramString string Param named paramString\n" " @param paramInt integer Param named paramInt\n" " @return returnString string Return named returnString\n" " @return returnInt integer Return named returnInt\n" " \"\"\"\n" " \n" " \"\"\"\n" " # Imported code :\n" " \n" " import json\n" " d = json.loads(jsonstr)\n\n" " # To use the input params, simply use d[\"paramString\"] d[\"paramInt\"] \n" " # Your code here\n\n" " ret_dict = {}\n" " ret_dict[\"returnString\"] = \"\"\n" " ret_dict[\"returnInt\"] = \"\"\n" " return json.dumps(ret_dict)\n" " \"\"\"\n" " \n" " return {\n" " \"returnString\": \"string\",\n" " \"returnInt\": \"integer\"\n" " }\n" " ") matches = re.search(regex, test_str, re.IGNORECASE) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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