Re: [boost] Re: any interest in a foreach looping construct?

From: Douglas Gregor (gregod_at_[hidden])
Date: 2003-10-09 22:15:35

On Thursday 09 October 2003 03:05 pm, Eric Niebler wrote:
> To recap, I'm suggesting the addition of BOOST_FOREACH to make it
> trivial to write loops over sequences and containers of various sorts.
>
> Typical usage:
> std::list<int> int_list;
> ...
> BOOST_FOREACH( int &i, int_list )
> {
>       // mutates the int in the list:
>       i += 20;
>       // break works as you would expect
>       if ( i == 100 )
>           break;
> }

I either love it, or I hate it, but I can't tell which :)

It looks technically sound, and I have no worries about that. I almost said 
that I prefer std::for_each, but that's not always true: there are some 
things that are just too hard to write inline with lambda/bind, too trivial 
to make into a separate function object (even though I'm a _huge_ fan of 
doing that), and writing the darned 'for' loop takes up two lines because 
'const_iterator' and 'typename' are so darned long. 

So overall I think I might like it. I gripe about macros as much as the next 
guy, but I do think there are cases where BOOST_FOREACH is cleaner than any 
of the alternatives. 

        Doug