Re: [boost] [conversion] review

Subject: Re: [boost] [conversion] review
From: Joshua Juran (jjuran_at_[hidden])
Date: 2011-08-31 04:11:53

On Aug 29, 2011, at 3:09 PM, Phil Endecott wrote:

> Gordon Woodhull wrote:
>> If I had to write a conversion function, I would rather write it  
>> as an overload of a general-purpose converter, rather than giving  
>> it some ugly typeA2TypeB name.
>
> Why is e.g. rgb_to_cmyk() "ugly"?

        cmyk_t cmyk = rgb_to_cmyk( rgb );

That's why.  Compare:

        cmyk_t cmyk = cmyk_from_rgb( rgb );

> Is it because it is C, and C syntax is ancient history that must be  
> purged from modern C++?

In the absence of parameterization in the caller (where the called  
function must be a template), a plain function has the advantage of  
looser coupling:  You only need the function prototype in scope,  
whereas to call a function template you need to have the  
specialization, (each of) which in turn needs the template  
declaration.  If you touch the header defining the template (or  
something else it includes), every user of every specialization needs  
to be recompiled.

Then again, I'm biased, since one of the compilers I support  
sometimes refuses to inline functions when templates are involved,  
and larger include sets dramatically slow down compiling, because I/O  
is expensive.

I agree with consistent naming, but I don't see <> and :: as  
inherently superior punctuation to _.

Josh