Re: for S'Image use Func??

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Fri, 07 May 2010 14:27:35 +0200, Robert A Duff  
<bobduff@shell01.theworld.com> a écrit:

> "Randy Brukardt" <randy@rrsoftware.com> writes:
>
>> I actually don't buy the need for the Assert pragma in the first place:  
>> such
>> checks are rarely expensive and thus should simply be part of the code
>> always.
>
> If they're not expensive, then you're not using it enough.  ;-)
Hihi, nice

> Also, the other advantage of pragma Assert over an Assert
> procedure is that you can put the pragma in declarative parts
> and package specs.
That's what I like to do too : define Assert pragmas in package spec, so  
that it can be used to derive some property in the implementation or in  
some other part of the specification. This express coherence between some  
elements or other things (there are things which cannot be expressed with  
type properties), on which you can rely to say “this and this, is valid,  
because of that (the Assert pragma somewhere)”. I find it useful to safely  
drop some runtime check whenever something must be fast or is looped  
thousands of times, or even simply to be sure something is OK (no need for  
execution speed requirements to wish that). If the assumptions are wrong  
and so what is derived from these too, well, the package simply raise an  
exception at elaboration instead of behaving oddly.

-- 
No-no, this isn't an oops ...or I hope (TM) - Don't blame me... I'm just  
not lucky