Re: [boost] New libraries implementing C++11 features in C++03

Subject: Re: [boost] New libraries implementing C++11 features in C++03
From: Dean Michael Berris (mikhailberis_at_[hidden])
Date: 2011-11-24 11:40:34

On Fri, Nov 25, 2011 at 3:23 AM, Thomas Klimpel
<Thomas.Klimpel_at_[hidden]> wrote:
> Dean Michael Berris wrote:
>>>> There's *exactly* the same number of lines in a local function as
>>>> there is with a class/namespace function. What am I missing?
>>>
>>> I'm actually also asking myself what I'm missing. Everybody seems to
>>> claim that a namespace function provides the same functionality as a
>>> local function.
>>
>> [...]
>> It's not that complicated.
>>
>> The first approach is the way we've been doing it with normal C++. It
>> works. It's not broken.
>>
>> I don't see why we'd ever need Boost.Local at all.
>
> OK, now I understand what you are missing. An important part of the functionality of Boost.Local is to capture variables from the enclosing function. Some even argued that C++ will never have true local functions, because you still have to specify the names of the variables from the enclosing function that you want to capture.
>

int i;
bool b;
long l;
auto local_function = [i, b, l](std::string const & s) {
  // do what I want here.
}
// use local_function somewhere else

Hmmm?

Or better yet, works now:

namespace foo {
  void non_local_function(int i, bool b, long l, std::string const & s) {
    // do what I want here.
  }

  void f(std::vector<double> const &v) {
    int i;
    bool b;
    long l;
    for_each(begin(v), end(v), bind(&non_local_function, i, b, l, _1));
  }
}

See, no voodoo required here.

> Of course, if you don't need to capture any variable from the enclosing function, using Boost.Local will only make your code more ugly.
>

I agree.

Now, do I still miss anything?

Cheers

-- 
Dean Michael Berris
http://goo.gl/CKCJX