[boost] Re: Formal Review: FOREACH macro

From: Eric Niebler (eric_at_[hidden])
Date: 2005-05-02 11:31:45

Andy Little wrote:
> 
> "Eric Niebler" <eric_at_[hidden]> wrote
> 
>> What about nested invocations for BOOST_FOREACH:
>>
>>     int a[100][200];
>>     int sum = 0;
>>
>>     BOOST_FOREACH(int (&x)[200], a)
>>         BOOST_FOREACH(int i, x)
>>             sum += i;
>>
>> ?
> 
> 
> Its a fair point but  just as  possible the other way:
> 
>        FOR_EACH(a){
>            BOOST_AUTO(& x, *_); // or int (&x)[200]  = *_;
>            FOR_EACH(x)
>                sum += *_;
>        }
> 

Andy, I think you are arguing for a design which is untenable. I would 
not accept a dependency on BOOST_AUTO, and I would not require users to 
register types and iterators with Boost.Typeof in order to use 
BOOST_FOREACH. You're trying to make BOOST_FOREACH easier to use, and I 
appreciate that, but an anology about babies and bathwater seems 
appropriate here.

-- 
Eric Niebler
Boost Consulting
www.boost-consulting.com