enum c++
Author
enum a1
{
A =1,
B
};
enum a2
{
C =1,
D
};
Can I use A and C interchangebly? Hello(enum a1); Would the compiler start complaining at Hello(C)
No you can't use them interchangebly like so. Yes the compiler will complain because C is not part of enum a1. But, as always, there is a way around this ... which you should not take by the way.
PS: Is refues to mention that you could have a brute force cast to cast type a2 to type a1 because. Its ugly enough to make ints from an enum and if you encounter a code line where you want to do so it is most likely you suffered from bad overall code design and should redesign this particulay code leading to this scenario.
enum a1 { A = 1, B };enum a2 { C = 1, D };void myFunction1(a1 value);void myFunction2(int value);int main(){ myFunction(C); // does not even compile m<Function2((int)(C)); // does compile and work as expected (if you expect to have same results for A and C) but is ugly return 0;}PS: Is refues to mention that you could have a brute force cast to cast type a2 to type a1 because. Its ugly enough to make ints from an enum and if you encounter a code line where you want to do so it is most likely you suffered from bad overall code design and should redesign this particulay code leading to this scenario.
I have to ask... why did you ask this question? It seems to me writing a test program to find out for yourself would have taken no more than 30 seconds...
Author
Quote:I have to ask... why did you ask this question? It seems to me writing a test program to find out for yourself would have taken no more than 30 seconds
Usually the error descriptions the compiler is bringing up are stupid/don't help much when you're learning stuff. (I don't what to find out only if this compiles or not [which I could have figured out myself], I also want to know why it does/doesn't compile)
Quote:Original post by CalinQuote:I have to ask... why did you ask this question? It seems to me writing a test program to find out for yourself would have taken no more than 30 seconds
Usually the error descriptions the compiler is bringing up are stupid/don't help much when you're learning stuff. (I don't what to find out only if this compiles or not [which I could have figured out myself], I also want to know why it does/doesn't compile)
int main () { enum Foo { foo }; enum Bar { bar }; Foo phoo = bar;}error: cannot convert `main()::Bar' to `main()::Foo' in initializationThe question is, how far does your "why" range? Is the above error message enough? Do you want to know that enums in C++ are typesafe? Do you want to know that enums are defined in "ISO/IEC 14882:2003" in section 7.2, "Enumeration declarations", with Item 4 stating
Quote:Each enumeration defines a type that is different from all other types, or do you need relevant sections about type safety and implicit conversion in C++?
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