🚀 go-pugleaf

In article <4dlrn5$81e@gabi.gabi-soft.fr>, J. Kanze <kanze@gabi-soft.fr> wrote:
>John Winters (john@polo.demon.co.uk) wrote:
>|> In article <KANZE.96Jan17121659@slsvewt.lts.sel.alcatel.de>,
>|> James Kanze US/ESC 60/3/141 #40763 <kanze@lts.sel.alcatel.de> wrote:
>|> [snip]
>|> >
>|> >Originally, the C standard was going to allow this; in fact, it was
>|> >going to allow all casts which added const anywhere in the type.  Then
>|> >someone pointed out that the conversion 'char ** -> char *const *' was
>|> >unsafe.  As a result, the wording was changed to only allow adding the
>|> >const at the top level.
>
>|> Interesting.  Could you enlighten us (well, me anyway) as to *why* it
>|> is unsafe.  I don't find it immediately obvious.
>
>As another poster has already pointed out, I gave the wrong conversion
>as unsafe.  (That's what comes of typing faster than you think.)
>-- 

But that wasn't what caused me to be unable to understand.  Even with the
correction I still couldn't see it without following the explanation
very closely.  An amusing little hole - reminds me of group theory.

John

-- 
John Winters.  Wallingford, Oxon, England.