[Boost-users] Re: FOREACH with maps

From: Dave Steffen (dgsteffen_at_[hidden])
Date: 2005-05-11 11:01:26

Eric Niebler writes:
 > Dave Steffen wrote:
 > > If anyone's interested: I'm playing with the idea of extending FOREACH
 > > in a way so that, instead of having a pair<>, you've got two separate
 > > variables for key and value.  Maybe something like:
 > > 
 > > map<int,int> m;
 > > ...
 > > FOREACH_PAIR(int key, int value, m)
 > > { ... }
 > > 
 > > I'm having a very moderate amount of success.  Anyone else playing
 > > with this sort of thing?
 > > 
 > 
 > 
 > Can't find the reference now, but someone suggested using tie() from the 
 > tuples library for this:
 > 
 > int key, int value;
 > BOOST_FOREACH(boost::tie(key, value), m)
 > { ... }

 Ah, yes, this is the sort of thing I was after.  I'll look into it.

 Every loop I've written for the past two weeks has turned out to be
 an iteration over a map of some sort; they are, now, all FOREACH
 loops.  Being the lazy sort of programmer I am, I'm now looking for
 ways to customize FOREACH to make iteration over maps easier.

 Thanks very much! 

----------------------------------------------------------------------
Dave Steffen, Ph.D.       "The only justification for our concepts and 
Software Engineer IV       systems of concepts is that they serve to 
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dgsteffen_at_[hidden]