Classes and class hierarchies
C.170
If you feel like overloading a lambda, use a generic lambda
Reason
You cannot overload by defining two different lambdas with the same name.
Example
void f(int);
void f(double);
auto f = [](char); // error: cannot overload variable and functionauto g = [](int) { /* ... */ };
auto g = [](double) { /* ... */ }; // error: cannot overload variablesauto h = [](auto) { /* ... */ }; // OKEnforcement
The compiler catches the attempt to overload a lambda.
C.union: Unions
A union is a struct where all members start at the same address so that it can hold only one member at a time. A union does not keep track of which member is stored so the programmer has to get it right; this is inherently error-prone, but there are ways to compensate.
A type that is a union plus an indicator of which member is currently held is called a tagged union, a discriminated union, or a variant.
Union rule summary: