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

/
/
gm

Test String

Substitution

Processing...

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"(\w+\s*\n*=\s*\n*)\{\n*\s*`((?:[^`](?!(?:\$\{|\n|(?:'[^`]*\"|\"[^`]*'))))*)`\n*\s*\}" test_str = ("// Match!\n" "<Component1\n" " // Using backticks without utilizing their functionalities\n" " className={`flex justify-center items-center gap-2`}\n" " description={``}\n" " content={\n" " `These backticks are unnecessary`\n" " }\n" " // This is a crime, but I did take it into account\n" " horrendousFormatting\n" " =\n" " {`Please never do something like this`}\n" "/>\n\n" "// Multiple matches in a single line\n" "<svg width={`100%`} height={`100%`} />\n\n" "// Cases where this regex won't match:\n" "<Component2\n" " // Non-string property\n" " disabled={isDisabled}\n" " // Quotes/Single quotes with unnecessary brackets\n" " // (I have another regex that's better adapted for this!)\n" " href={\"https://regex101.com/library/l9MPcQ\"}\n" " // String templating\n" " className={`flex items-center justify-center size-5 ${iconColor}`}\n" " // Escaping BOTH \" AND ' IN THE SAME STRING with backticks\n" " title={`This string's backticks are \"justified\"`}\n" " // Escaping line breaks with backticks\n" " description={\n" " `String with\n" " a line break`\n" " }\n" " // \"/'/` mismatch\n" " content={`Yeah this will turn the rest of your file into a string\"}\n" ">\n" " {icon}\n\n" " // No match since this is not a property\n" " {` `}\n\n" " (Some people do this instead of using &nbsp;)\n" "</Component2>\n") subst = "$1\"$2\"" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # 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