为什么在Swift的String API中将Unicode包含为编码？

Question

I read this very important blog regarding string encodings .

After reading it I realized that unicode is a standard of mapping characters to code points which are integers. How these integers are stored in memory is an entirely different concept. This is where .utf8 , .utf16 come into play, defining the way we store these integers in memory.

In the Swift String API there is a method which gives us the data bytes used to represent the String in various encodings:

func data(using encoding: String.Encoding, allowLossyConversion: Bool = false) -> Data?

The first parameter to this method is of Type String.Encoding . This struct Encoding has an encoding declared as:

static let unicode: String.Encoding

Now suddenly the method can give me data representation of the String using the encoding .unicode

Now this is in fact opposite to what I concluded after reading the mentioned blog. Its giving me data representation of a string, even thought unicode does not provide me details of how it can be stored.

Can any one tell me what am I missing here? I am really confused now.

Answer 1

String.Encoding.unicode is the same as String.Encoding.utf16

print(String.Encoding.unicode)
print(String.Encoding.utf16)

The above prints:

• Unicode (UTF-16)
• Unicode (UTF-16)