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Subject: Re: [Boost-users] BOOST_FOREACH with Index
From: OvermindDL1 (overminddl1_at_[hidden])
Date: 2009-12-13 21:11:50

On Sun, Dec 13, 2009 at 6:41 PM, Nat Goodspeed <nat_at_[hidden]> wrote:
> Eric Niebler wrote:
>>>>    Why not:
>>>>     int index = 0;
>>>>     BOOST_FOREACH(const Foo &f, foos)
>>>>     {
>>>>       // ... stuff ...
>>>>       ++index;
>>>>     }
>> What value BOOST_FOREACH has comes primarily from its ability to simplify
>> something that's already pretty darn simple -- a plain for(;;) loop. I
>> strongly resist any effort to make BOOST_FOREACH more complicated, unless
>> the wins are truly significant. In this case, I don't think they are.
> Maybe this shouldn't be a BOOST_FOREACH feature at all. As with Python's
> builtin enumerate() function, maybe what we want here is an iterator adapter
> that dereferences to a std::pair<index_type, original_iterator_value_type>?

Ooo, that makes sense, as long as it can still be done quickly (ala
the in index = 0; example above):
BOOST_FOREACH(size_t i, const Foo &f, ENUMERATE(foos))

Or maybe:
BOOST_FOREACH_ENUMERATE(size_t i, const Foo &f, foos)

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