Re: [PATCH] cleaning before = assignment lotuswordpro/source/filter/xfilter/xfparastyle.cxx

Thank you David for the hint!
I re read the "An in-depth explanation" part of
http://stackoverflow.com/questions/3279543/what-is-the-copy-and-swap-idiom/3279550#3279550,
it's great ! I understood when and above all how the memory is cleaned.

About your multidimalgorithm, what would be the problem if it'd be changed
like this ? (to sum up: passing parameter by value to optimize)

/include/mdds/flat_segment_tree.hpp

 flat_segment_tree<key_type, value_type>&
operator=(flat_segment_tree<key_type, value_type> other);

/include/mdds/flat_segment_tree_def.inl 
        template<typename _Key, typename _Value>
        flat_segment_tree<_Key, _Value>&
        flat_segment_tree<_Key, _Value>::operator=(flat_segment_tree<_Key, _Value>
other)
        {
            swap(copy);
            return *this;
        }

this part of
http://stackoverflow.com/questions/3279543/what-is-the-copy-and-swap-idiom/3279550#3279550
made me think about this:
Observe that upon entering the function that all the new data is already
allocated, copied, and ready to be used. This is what gives us a strong
exception guarantee for free: we won't even enter the function if
construction of the copy fails, and it's therefore not possible to alter the
state of *this. (What we did manually before for a strong exception
guarantee, the compiler is doing for us now; how kind.)

Is this design pattern without flaw (does it exist ? :-)) and be applied in
every case in LO code ?

Thank you too Stephan about the refs. First I must finish Stroustrup's book
and the way is long because I never really coded in C++ just some Java (when
it was in 1.3) and few C and VB.

Julien

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