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Subject: [ggl] pre-/post-increment op on iterators
From: Bruno Lalande (bruno.lalande)
Date: 2009-04-28 08:42:54

> typedef vector<pair<int, pair<float, float> > > v_t;
> // use v_t later in the code
> ...
> BOOST_FOREACH(v_t::value_type p, v)

If the typedef is already needed somewhere else, it's a solution. The
problem is that there exist more and more tools (make_xxx functions,
auto keyword or BOOST_AUTO, etc...) that make those typedefs less and
less often needed.

> Yes, I found it convenient too.
> However, I can understand the rationale behind BOOST_FOREACH.
> Even if it does require explicit use of value_type, on the other
> hand it frees you from knowledge about how container/collection is
> being iterated. Iteration is hidden as it is by algorithms.
> Second, if functor introduces extra entities into code,
> and in some cases it may make code less readable/understandable.
> BOOST_FOREACH is handy as replacement for simple loop, plus it
> provides nice genericness.

Yep, all approaches have their drawbacks and advantages, indeed. So I
don't really bother if somebody uses one or the other, I simply wait
for the concept-based C++0x for_each that will solve everything :-)


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