Re: [boost] [function] function wrapping and exception safety recap

Subject: Re: [boost] [function] function wrapping and exception safety recap
From: Domagoj Saric (dsaritz_at_[hidden])
Date: 2010-10-19 16:45:43

"Emil Dotchevski" <emil_at_[hidden]> wrote in message 
news:AANLkTikGfE0KcMXjPMpqL-+12rUbouOrVGr1Rfgr_m_-_at_mail.gmail.com...
> On Tue, Oct 19, 2010 at 12:34 AM, Domagoj Saric <dsaritz_at_[hidden]> wrote:
>> Just like in the case of shared_ptr, I still don't buy this argument...: 
>> why
>> would replacing hardcoded dynamic behaviour with configurability through
>> policies 'interfere' with type erasure?
>
> Because function<T,A1> is not the same type as function<T,A2>.

And? So is function<T1> not the same type as function<T2>...what difference 
does that make? The point is, AFAIK, to erase the type of the object you put 
into a boost::function<> instance, not the type of boost::function 
itself...after all unlike in Objective-C(++) in C++ everything has _some_ 
type in the end...

If one wants to fix(ate) one or all template parameters of boost::function 
in an interface (for example to what they are now implicitly hardcoded when 
you have no option to choose) one is perfectly free to do so (thus e.g. 
transforming your function<T, A1> to function<T>)...
...the difference is that the user has the >_option_< (or is time to be 
pathetic and say "freedom") to choose...

You can always go from "freedom" to "rule of thumb"/"happy Joe Sixpack" but 
not vice verse...

--
"What Huxley teaches is that in the age of advanced technology, spiritual
devastation is more likely to come from an enemy with a smiling face than
from one whose countenance exudes suspicion and hate."
Neil Postman