digitalmars.D.learn - casting between structs
- "Mariusz `shd` =?UTF-8?B?R2xpd2nFhHNraSI=?= <alienballance gmail.com> (24/24) Dec 18 2013 I'd like to reinterpret data as different type without copying.
- bearophile (5/6) Dec 18 2013 One thing to remember when casting, is that when you cast
I'd like to reinterpret data as different type without copying. extern(C) struct A{ /* */ } struct B { A a; alias a this; } extern(C) A* f1(){ /* */ } B* f2() { return cast(B*) f1(); } Assuming that i cast() correct state, i'd like to know if: * it's currently safe * it's guaranteed to be safe in the future * there any precautions in using this pattern Most important thing for me is a type-check, but defining operators ( since they can't be external ) would be nice too. I'm asking because i'd like to use this pattern a lot in my code, and with my limited knowledge it's good to get some feedback of more experienced. Ps. In situations when i return by value instead of pointer - will memory copying be optimized away ?
Dec 18 2013
Mariusz `shd` GliwiĆski:* it's currently safeOne thing to remember when casting, is that when you cast const/immutable to mutable, then you can't mutate the data. Bye, bearophile
Dec 18 2013