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

/
/
gms

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /(?x) .+(?:Sub|Function)\ (\w+)\( # method declaration (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) (?: # start of parameter pattern [\w\W]*?(?<=\b) # parameter may be preceded by ByVal or Optional keywords ([a-z]\w+)+ # parameter starts with a lower case .*? # parameter may be followed by its type declaration (?:=\ ([^\,]+)){0,1} # optional parameters may be followed by default value, it is captured to be used in method call (?:,|\)) # parameter is followed by , or ) ){0,1} # end of parameter pattern (may be copy-pasted infinitely to capture all parameters) /m str = 'Public Function BrowseToDictTreeNode(ByVal rootNode As Scripting.Dictionary, ByVal browseKey As String, ByVal nodeUrl As String, _ Optional ByVal urlSlash As String = "/", Optional ByVal childrenKey As String = "Children", _ Optional ByVal startAtLevel As Integer = 1) As Scripting.Dictionary ' subst = '#Sub call\\n$1 $2:=$3, $4:=$5, $6:=$7, $8:=$9, $10:=$11, $12:=$13, $14:=$15, $16:=$17, $18:=$19, $20:=$21, $20:=$21, $22:=$23, $24:=$25\\n\\n#Function call\\n$1($2:=$3, $4:=$5, $6:=$7, $8:=$9, $10:=$11, $12:=$13, $14:=$15, $16:=$17, $18:=$19, $20:=$21, $20:=$21, $22:=$23, $24:=$25)\\n\\n#Recursive Sub call\\n$1 $2:=$2, $4:=$4, $6:=$6, $8:=$8, $10:=$10, $12:=$12, $14:=$14, $16:=$16, $18:=$18, $20:=$20, $22:=$22, $24:=$24, \\n\\n#Recursive Function call\\n$1($2:=$2, $4:=$4, $6:=$6, $8:=$8, $10:=$10, $12:=$12, $14:=$14, $16:=$16, $18:=$18, $20:=$20, $22:=$22, $24:=$24, )' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html