Essentially there is special wording all around the c++17 draft standard that gives std::byte the same properties with regard to aliasing as char and unsigned char. To give you an example, the the C++17 standard, [basic.lval] p8 states: If a program attempts to access the stored value of an object through a glvalue of other … Read more
From the current Standard draft ([basic.types.general]/2): For any object (other than a potentially-overlapping subobject) of trivially copyable type T, whether or not the object holds a valid value of type T, the underlying bytes ([intro.memory]) making up the object can be copied into an array of char, unsigned char, or std::byte ([cstddef.syn]). If the content … Read more
A class with an unsigned char member would not be required by the standard to be the same size or alignment as unsigned char. Whereas the standard requires that enumerations be the same size and alignment as their underlying types. Now, the standard could have simply declared that it is a class type with no … Read more
You are perhaps misunderstanding things. byte is very much intended for “accessing memory”. You are intended to use the type when the storage is just a sequence of bytes rather than an array of characters. Iostream types cannot be specialized with byte, since they’re designed around characters as their interface. That is, they do not … Read more