Motivation The simplistic answer is that a C++ module is like a header that is also a translation unit. It is like a header in that you can use it (with import, which is a new contextual keyword) to gain access to declarations from a library. Because it is a translation unit (or several for … Read more
This is called the three-way comparison operator. According to the P0515 paper proposal: There’s a new three-way comparison operator, <=>. The expression a <=> b returns an object that compares <0 if a < b, compares >0 if a > b, and compares ==0 if a and b are equal/equivalent. To write all comparisons for … Read more
Short answer No. Explanation [namespace.std] says: Let F denote a standard library function ([global.functions]), a standard library static member function, or an instantiation of a standard library function template. Unless F is designated an addressable function, the behavior of a C++ program is unspecified (possibly ill-formed) if it explicitly or implicitly attempts to form a … Read more
(The approach of the better_enums library) There is a way to do enum to string in current C++ that looks like this: ENUM(Channel, char, Red = 1, Green, Blue) // “Same as”: // enum class Channel : char { Red = 1, Green, Blue }; Usage: Channel c = Channel::_from_string(“Green”); // Channel::Green (2) c._to_string(); // … Read more
What is it? A span<T> is: A very lightweight abstraction of a contiguous sequence of values of type T somewhere in memory. Basically a struct { T * ptr; std::size_t length; } with a bunch of convenience methods. A non-owning type (i.e. a “reference-type” rather than a “value type”): It never allocates nor deallocates anything … Read more