Documented all symbols in Utilities.swift

Sources/CSV/Utilities.swift

@@ -1,17 +1,36 @@
 // MARK: - String <-> Bytes conversion
 extension CustomStringConvertible {
+
+    /// Converts the value's string description to its byte representation.
     var bytes: [UInt8] {
         return Array(self.description.utf8)
     }
 }
 
 extension String {
+
+    /// Creats a new `String` instance from an array of bytes.
+    ///
+    /// - Parameter bytes: The byte array that will be the new string value.
     init(_ bytes: [UInt8]) {
         self = String(decoding: bytes, as: UTF8.self)
     }
 }
 
 extension Array where Element == UInt8 {
+
+    /// Escapes raw escape chraacters in a byte array.
+    ///
+    /// The characters are escaped by each escape charcter in the array being replaced with 2 escape charcters, so a string like this:
+    ///
+    ///     "\o/"
+    ///
+    /// If escaped with the `\` chracter, would become:
+    ///
+    ///     "\\o/"
+    ///
+    /// - Parameter character: The byte that represents the character to escape.
+    /// - Returns: The bytes of the string, with each raw escaped character being escaped.
     func escaping(_ character: UInt8?) -> [UInt8] {
         guard let code = character else {
             return self
@@ -26,9 +45,18 @@ extension Array where Element == UInt8 {
 
 // MARK: - Coding Key Interactions
 extension Dictionary where Key == String {
+
+    /// Extracts the value from a dictinary, using a `CodingKey` for the key.
+    ///
+    /// - Parameter key: The coding key to use as the key in the dictionary.
+    /// - Returns: The  value for the key passed in.
+    /// - Throws: `DecodingError.valueNotFound` if the value for the given key is missing,
     func value(for key: CodingKey)throws -> Value {
         guard let value = self[key.stringValue] else {
-            throw DecodingError.keyNotFound(key, DecodingError.Context.init(codingPath: [key], debugDescription: "No value found for key '\(key.stringValue)'"))
+            throw DecodingError.valueNotFound(Value.self, .init(
+                codingPath: [key],
+                debugDescription: "No value found for key '\(key.stringValue)'"
+            ))
         }
         return value
     }