Re: Ada Annoyances

["Randy Brukardt" <randy@rrsoftware.com>]

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<raph.amiard@gmail.com> wrote in message 
news:8d3aff06-82df-485f-89e5-a50c326aab05@googlegroups.com...
Le mercredi 21 juin 2017 18:12:53 UTC+2, Dmitry A. Kazakov a écrit :
>...
>It could very well be argued that the C++ choice is a lot better.

Well, in the sense that you can argue anything. Some people argue the earth 
is flat, too.

>Most of the time, you never want to call a possibly dispatching method in 
>without dispatching.

This seems to be a viewpoint that comes from taking OOP religious dogma as 
some sort of fact. A much more sensible statement is that "most of the time, 
you want to call the correct subprogram body for your object". A sensible 
programmer will never care how that is determined or which mechanism is used 
to implement that. And the fact that a statically bound call is faster than 
a dynamically bound call suggests the former ought to be used.

>Ada gives you a little bit more flexibility, at the cost of being much more 
>error prone,
>because it's easy to make a non dispatching call instead of a dispatching 
>one. Not
>a good point for Ada !

Yeah, it's terrible that Ada avoids errors and ignores dogma.

A more sensible take on this is that it is insane to put the burden of what 
can be called with a dispatching call onto a library designer. The vast 
majority of routines in Claw have no (obvious) good reason to be called as 
dispatching calls. But I don't want to claim to know how every user of Claw 
might want to use it, so if Ada had followed the C++ rule, every routine 
would have had to be marked virtual, effectively making everything more 
expensive. Library designers are not omnipitent!

                              Randy.