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From: zrb on 12 Dec 2009 16:26
I am aware of the std::function solution... but I was wondering if it
is possible to avoid it.

auto foo = [](int x){return x+1;};
auto bar = [](int x){return x+1;};

The example given above that mentioned that "foo" is not the same type
as "bar" sums up the problem. In fact, when I change the code to...

21 typedef decltype([=]() -> int {return 0;}) getterXType;
22
23 getterXType getterX()
24 {
25 return ([=]() -> int {return this->m_x;});
26 }

....I get the following error.

main.cpp: In member function �<lambda()>& LambdaMember::getterX()�:
main.cpp:25:45: error: invalid initialization of non-const reference
of type �<lambda()>&� from an rvalue of type �LambdaMember::getterX
()::<lambda()>�

This is a type conversion error... despite having the same signature,
the two lambda functions are not of the same type, since the one
inside "getterX()" is actually a class type local to the function.

While I am happy with the std::function approach... does anybody see
any potential problems?


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From: Mathias Gaunard on 12 Dec 2009 22:31
On 13 d�c, 09:26, zrb <zraj...(a)gmail.com> wrote:

> While I am happy with the std::function approach... does anybody see
> any potential problems?

Prefer std::nested_function, or whatever its name is, that's better.


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