Subject: Re: [boost] [optional] generates unnessesary code for trivial types
From: Nevin Liber (nevin_at_[hidden])
Date: 2012-01-27 17:10:48
On 27 January 2012 12:57, Simonson, Lucanus J
> Optional was implemented to be safe and slow because it was targeting safe and slow use cases.
You are saying it is *deliberately* slow??
> For POD types and anything that has a default constructor a std::pair<bool, T> seems fine to me.
I don't want to write a different style of code depending on whether
or not a type T is default constructible. I can't easily pass things
like this to templates because I have to write special cases all over
the place. Optional models my intent.
I want to take advantage of RVO.
Some things that are default constructible are still very expensive to
construct (such as std::deque under gcc).
When you initialize class members, do you use member intializer lists
for default constructible types or do you just throw a bunch of
assignments in the body of the constructor? If the former, why do you
do it, given that default construction followed by assignment "seems
fine" to you?
-- Nevin ":-)" Liber <mailto:nevin_at_[hidden]> (847) 691-1404
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