On 1/27/15 5:57 AM, Walter Bright wrote:
On 1/26/2015 11:06 AM, Steven Schveighoffer wrote:
Is there a good reason why we shouldn't allow the duplicate
declaration in
multiple modules? I understand for D symbols -- those are actually
different
symbols.
D's interface to C and C++ does not adopt C and C++ semantics, in
particular, it does not adopt C and C++ name lookup rules, function
overloading rules, template instantiation rules, etc. This is on purpose
to reduce the complexity of the language.
I never said anything about C++. I don't see how that is relevant. C has
no overloading rules or template instantiation rules.
As in C and C++, it is up to the D programmer to follow the One
Definition Rule when interfacing with those languages. Declaring the
same function in multiple modules is a bad idea.
The problem I see is that C bindings are easy to make. If I need to
reference I function, I just declare it. If some other library writer
needs the same function, he declares it. But now, if anyone wants to use
both libraries, you have to pick one or the other, even though they are
the same.
I understand the idea behind keeping the lookup rules consistent. But C
lookup rules ARE simple.
I would say if two extern(C) declarations are identical (i.e. same
parameter types, same attributes), they don't conflict. What does this
break?
-Steve
