Re: NSUnarchiver extensions

[Richard Frith-Macdonald]

On Tuesday, February 26, 2002, at 02:58 PM, Pierre-Yves Rivaille wrote:

> I tried this before too, but it was segfaulting too (it is the same 
> problem as before, trying to access info without checking it is nil, 
> I've just corrected it in CVS).

Thanks.

> Anyway I just thought that the new methods could prove useful, but I 
> agree i might not be that useful outside tricky situations where other 
> cleaner tricks might also work.

Well, as far as policy on extending the framework goes, I used to think 
there were
two legitimate reasons for that -

1. functionality that the base library needs internally can be made 
public too - where
it's useful.

2. important functionality that has to be tightly integrated with the 
library in order
to get decent performance.

I no longer really believe that (1) is a good justification, and I'm 
really thinking
about how to separate out things that I was previously guilty of putting 
in (XML
parsing being the most obvious thing).  The increasing number of people 
wanting to
maintain portability with MacOS-X has been a major factor in my change 
of mind on this.

I still think that (2) is valid, but that the judgment of what is 
important should
not be too generous :-)