From: Powell, Gary (powellg_at_[hidden])
Date: 2004-03-04 12:05:25
>>Yeah, but do you propose to make local names visible inside the anonymous
>>function, or not? If you do, you open a big can of worms for implementations
>>(recursive nested functions, need I say more?), if you don't, BLL can still
>>do things that anonymous functions can not. Anonymous functors could help
>>some, but their syntax won't be quite as compact as your example above.
> Now, to complicate matters, what if I wish to access v in the
> inner anonymous function? Can you also do that? Example:
> std::for_each(vv.begin(), vv.end(),
> void (vector<int> const& v)
> std::for_each(v.begin(), v.end(),
> void (int x)
> cout << x << endl;
> do_fomething_with(v); // <<--here
> Joel de Guzman
This gets ugly. As you want to "import" only one the variables you declare. For the
previous example with std::accumulate.
template <class InputIterator,
T accumulate<InputIterator v,
while (v != l)
i = bin_op(i, *v++);
int i = 0;
unsigned long n = std::accumulate(
xs.begin(), xs.end(), 0UL,
auto (auto lhs, auto rhs)
return ( lhs + rhs.count) + i; // Which "i"!!!!
And this is where BLL wins big, it has a mechanism for importing variables into the fn.
And no I don't have a good solution for this.
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