struct X { X(int); X(const char*, int =0); X(int, int); }; void f(X arg) { X a = 1; // a = X(1) X b = "Jessie"; // b = X("Jessie",0) a = 2; // a = X(2) f(3); // f(X(3)) f({1, 2}); // f(X(1,2)) }
struct Z { explicit Z(); explicit Z(int); explicit Z(int, int); }; Z a; // OK: default-initialization performed Z b{}; // OK: direct initialization syntax used Z c = {}; // error: copy-list-initialization Z a1 = 1; // error: no implicit conversion Z a3 = Z(1); // OK: direct initialization syntax used Z a2(1); // OK: direct initialization syntax used Z* p = new Z(1); // OK: direct initialization syntax used Z a4 = (Z)1; // OK: explicit cast used Z a5 = static_cast<Z>(1); // OK: explicit cast used Z a6 = { 3, 4 }; // error: no implicit conversion