 
 public extension String {
 
+    /// A Boolean value indicating if all the characters are letters.
+    ///
+    /// - Returns: True, if all characters are letters. Otherwise, false.
     func isAlpha() -> Bool {
         return containsCharactersFound(in: .letters)
     }
 
+    /// A Boolean value indicating if all the characters are alphanumeric.
+    ///
+    /// - Returns: True, if all characters are alphanumeric. Otherwise, false.
     func isAlphanumeric() -> Bool {
         return containsCharactersFound(in: .alphanumerics)
     }
 
+    /// A Boolean value indicating if the string is capitalized.
+    ///
+    /// - Returns: True, if first character is uppercased. Otherwise, false.
     func isCapitalized() -> Bool {
         return self == capitalized
     }
 
+    /// A Boolean value indicating if the string's first character is lowercase.
+    ///
+    /// - Returns: True, if first character is lowercased. Otherwise, false.
     func isDecpitalized() -> Bool {
         return self == decapitalized()
     }
 
+    /// A Boolean value indicating if all the characters are lowercased.
+    ///
+    /// - Returns: True, if all characters are lowercased. Otherwise, false.
     func isLowercased() -> Bool {
         return self == lowercased()
     }
 
+    /// A Boolean value indicating if all the characters are numbers.
+    ///
+    /// - Returns: True, if all characters are numbers. Otherwise, false.
     func isNumeric() -> Bool {
         return containsCharactersFound(in: .decimalDigits)
     }
 
+    /// A Boolean value indicating if all the characters are uppercased.
+    ///
+    /// - Returns: True, if all characters are uppercased. Otherwise, false.
     func isUppercased() -> Bool {
         return self == uppercased()
     }


private extension String {

    static prefix func - (string: String) -> String {
        return string.replacingOccurrences(of: "_", with: " ").replacingOccurrences(of: "-", with: " ")
    }

    ///     print(string.trimRight(length: 7))
    ///     // Prints "Hello"
    ///
    /// - Parameter length: The number of characters to trim from the end of the string. If the provided length is greater than the original string, the original string is returned.
    /// - Returns: The right-trimmed copy of the string.
    @discardableResult
    func trimRight(length: Int) -> String {
