On Sat, Oct 04, 2008 at 05:09:47PM -0400, Bob Rogers wrote:
Content-Description: message body text
> From: "Patrick R. Michaud" <[EMAIL PROTECTED]>
> Date: Sat, 4 Oct 2008 09:41:22 -0500
>
> On Fri, Oct 03, 2008 at 09:47:38PM -0700, Larry Wall wrote:
> > On Fri, Oct 03, 2008 at 11:57:30PM -0400, Michael G Schwern wrote:
> > : What's the status of numeric upgrades in Perl 6? Is see the
> > : docs say "Perl 6 intrinsically supports big integers and rationals
> > : through its system of type declarations. Int automatically
> > : supports promotion to arbitrary precision" but it looks like it's
> > : doing the same thing as Perl 5.
> >
> > The status of numeric upgrades in Perl 6 is fine. It's rakudo that
> > doesn't do so well. :)
>
> Correct. I suspect that eventually the Rakudo developers will have
> to develop a custom set of PMCs for Perl 6 behaviors rather than
> relying on the Parrot ones.
>
> The Parrot behavior in this case may be closer than you think. After
> applying the patch below, I get the expected output from Rakudo:
>
> [EMAIL PROTECTED]> ./perl6 -e 'say 2**40'
> 1099511627776
> [EMAIL PROTECTED]> ./perl6 -e 'say 2**50'
> 1125899906842624
> [...]
>
> It does produces >300 spectest_regression failures, though, so I don't
> claim the patch is right.
One of the big problems with Parrot's n_* opcodes is that they
often assume that the type of the result should be the same as
the type of the first operand. So, given (Perl 6) code like
my @a = <abc def>;
say @a * 2147483648;
the PIR translation using n_mul fails because it doesn't
know how to n_mul a ResizablePMCArray:
$ cat v.pir
.sub main
## Perl 6: my @a = <abc def>;
.local pmc a
a = new 'ResizablePMCArray'
a[0] = 'abc'
a[1] = 'def'
## Perl 6: say @a * 2147483648
$P1 = n_mul a, 2147483648
say $P1
.end
$ ./parrot v.pir
MMD function __multiply not found for types (58, -99)
current instr.: 'main' pc 11 (v.pir:9)
$
All of the mechanisms I've been able to find in Parrot for
converting an arbitrary PMC to a number seem to result in
the code for infix:<*> that we have now. I'm open for
suggestions to improve this, though.
Pm
