Re: Struct vs Class, take II
There is one more major difference between structs and classes. structs can exist inside of an extern "C" block, classes may not.
Most people use structs to just store data instead of classes, simply because it's faster to write a struct that a class. It doesn't take long to type "public:" but why bother if you don't have to.
Re: Struct vs Class, take II
Quote:
Originally Posted by ninja9578
structs can exist inside of an extern "C" block, classes may not.
That is not true.
Re: Struct vs Class, take II
Quote:
Originally Posted by
ninja9578
There is one more major difference between structs and classes. structs can exist inside of an extern "C" block, classes may not.
Code:
extern "C"
{
class x
{
int y;
};
}
Code:
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Re: Struct vs Class, take II
Quote:
Originally Posted by
amira7
Besides the visibility of members,
Structs are value types and classes are reference types.
As you know, value types are allocated on the stack or inline as a part of another object while classes are allocated on the heap.
Struct is often a small object that needs to be treated like a primitive type while classes are normally used for implementation requiring more processing power. In other words, classes would normally be used to implement a piece of business logic, rather than to support data related or primitive-type objects.
I hope this clears it up a bit.
This is not true. None of it. amira7 is clearly a C# programmer or has somehow gotten confused, reading C# literature.
Re: Struct vs Class, take II
Okay, it shouldn't be used in a extern "C" block. Because if you do, it completely breaks all C compatibility.
Re: Struct vs Class, take II
Quote:
Originally Posted by
Chris_F
This is not true. None of it. amira7 is clearly a C# programmer or has somehow gotten confused, reading C# literature.
It's true in the sense that it describes common usage fairly well. But, as I noted in my first post, this usage is not stipulated by the C++ language.
In the book I mentioned (The Design and Evolution of C++, p. 76), Stroustrup explains why he did not keep the C-struct in C++. The reason is that he didn't want one simple and one advanced version of the same concept. He dropped the C-struct and made struct and class equals in order to keep the C++ language together.
Anyone is free to assign different roles to the struct and the class but that's just a question of convention and personal taste. In C++ "a struct is a class" and according to Stroustrup this notion has "stopped C++ from drifting into becoming a much higher-level language with a disconnected low-level subset".
So Stroustrup didn't want C++ to become two languages in one and that's why struct and class are now equals. But that doesn't prevent anyone, including me, from treating the struct as if it was the little brother of the class. Even Stroustrup himself subscribes to this usage. (The C++ Programming Language, 3'rd ed., p. 234).
Re: Struct vs Class, take II
Quote:
Originally Posted by
ninja9578
Okay, it shouldn't be used in a extern "C" block. Because if you do, it completely breaks all C compatibility.
Should only be a problem if you use a ctor/dtor, operator overloading, virtual functions, etc. All of which can be used with either struct or class.
