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Postings from September 2000
On Tue, Sep 19, 2000 at 08:41:34AM +1200, Christian Soeller wrote:
> > Finally as an overload expert what do you think about the proposals
> > to make arrays overloadable objects so one can say things like:
> >
> > @x = 3 * @y;
>
> Is this where RFC 231's suggestion for OO slicing comes in (see quote)?
>
> > For example,
> >
> > $matrix1->[2..5; 2..4] * $matrix2->[1,3,5; 11..64];
> >
> > would denote: create two new objects for the specified submatrices, apply (overloaded) multiplication to these objects. Such a
> > request is illegal for untie()d arrays; for tie()d arrays it is converted to a call to FETCH_SLICE in a scalar context.
> > (Alternative: introduce two new tie()d methods: FETCH_SUBOBJECT, STORE_SUBOBJECT.)
>
> or is this supposed to be othogonal?
Note the contexts: in my $matrix1->... proposals the things we
multiply are objects (scalars!). This C<*> in my example is the "usual"
overloaded C<*>.
While in
@x = 3 * @y;
C<*> is some strange "array-context multiplication".
> Another questing re RFC 231. Is it really required to make the
> syntactical distinction between ranges (..) and bi_ranges (...)? Some
> more explanation would be appreciated.
I do not see how else one can do it.
a) We want @arr[ $start .. $start + $items - 1 ] work for $items==0
too, right?
b) We want @arr[ 0 .. -1 ] to get all the elements of the array, right?
I see no way to distinguish these two situations except by using
different syntax...
Ilya
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