C99 has this nice thing where you can initialise structs inline with named members, so like:
struct A { int a, b, c; };
...
struct A a = ( struct A ) { .c = 1, .a = 2 };
printf( "%d %d %d\n", a.a, a.b, a.c ); // { 2, 0, 1 }
It's useful so it's not available in C++, but we can hack it together with variadic templates and pointer-to-members:
template< typename T >
T compound_literal() {
return T();
}
template< typename T, typename A, typename... Rest >
T compound_literal( A ( T::* m ), const A & v, const Rest & ... rest ) {
T t = compound_literal< T >( rest... );
t.*m = v;
return t;
}
...
A a = compound_literal< A >( &A::c, 1, &A::a, 2 );
I assume this breaks under even minimal C++ feature usage and the errors are the worst shit of my life but this post is a joke and you shouldn't use it anyway.