On 12/23/05, Juerd <[EMAIL PROTECTED]> wrote:
> Luke Palmer skribis 2005-12-23 16:16 (+0000):
> > However, I think that would be ignoring the amazing prevelance of the
> > shallow copy idioms in perl 5:
> > [ @array ]
> > { %hash }
>
> It's a great idiom. Not much typing, easy on the eyes and easy to
> understand.
>
> There's little, if any, reason to use a .clone method instead.
Uh, I was talking about shallow copy of arbitrary objects, not just of
arrays and hashes.
> > We could consider .clone to be the natural extension of this (and have
> > the above forms be its definition for Array and Hash).
>
> I think both shallow and deep should be possible, with an infinite
> amount of options in between. One hashref may be meant as a nested hash,
> while the other is meant as a reference to a conceptually separate hash.
> The first should be copied, the second not. How on earth we're going to
> let Perl know what we want is, in my opinion, much more interesting than
> what the default behaviour will be.
>
> Consider
>
> my %foo = (
> a => 41,
> b => 15,
> c => {
> bar => 1,
> baz => 1,
> quux => 0,
> },
> d => \%bar,
> );
>
> I'd want something that clones this, somewhere between shallow and deep.
> .<c> should be deep, but .<d> shallow. Perhaps this can be determined
> using some attribute, that for a referenced hash defaults to the
> opposite of what it defaults to for a literal anonymous hash.
That's an interesting idea. A "deep reference". I imaging you're
suggesting this because you had a situation in real life where it came
up. Can you describe that?
Luke
