On Tue, Feb 19, 2013 at 5:33 PM, Christian Henning <chhenning@gmail.com>wrote:
What I *think* you want is for operator++ to conditionally call _reader->skip (if the previous operator++ had not been followed by a operator*), while operator* should conditionally call _reader->read (depending on if there had been an intervening operator++ after the previous operator*). So, I think you'd need 2 boolean flags.
Does that make sense? (I might objectively not be making sense, I'm not sure.)
I think your thinking makes sense! I have updated the code here:
http://svn.boost.org/svn/boost/trunk/boost/gil/extension/io/detail/scanline_...
If you could have a look that would be very kind.
I had a quick look, and I immediately noticed that you (still, I guess?) are incrementing the _pos member upon dereferencing the first time...is there some reason you don't increment it unconditionally in operator++? I'm guessing the end result is the same, given the pair of boolean flags encoding the state, but it's a "code surprise", which increases the cognitive overhead to read it :) - Jeff