Am Mittwoch, 23. Mai 2007 04:05 schrieb Patrick R. Michaud:
> Here's the perl 6 code:
>
> my $a = sub { ... }; # $a is a subroutine reference
> my $b := $a;
> # ...;
> $a = 4; # $a is now an Int
>
> How to do the above in PIR if we can't morph a Sub?
I may be not totally uptodate with the recent implementation changes. But I've
repeatedly urged a clear separation between variables and values. Obviously
the mixture of these is still the current way to go. Anyway: I'd translate
above code to the following pseudocode:
.var '$a' = .value '.sub ... '
.var '$b' = .var '$a'
.var '$a' = .value '4'
There is no need for any morph or such operation. Sometimes the implementation
needs an additional indirection though, but there are already a lot of these
indirections (think of the pmc_ext or even data pointers in the PMC).
All values can be shared and are readonly, well, variables are changing. Thx
to listening.
leo
