On Monday, October 27, 2003, at 03:26 pm, Melvin Smith wrote:
At 02:56 PM 10/27/2003 +0000, Arthur Bergman wrote:So I am currently trying to do a Perl5LVALUE pmc, a stumbling block is however that I need to pass the PMC the thing that it is lvalueling, I was planning to use the pmc data field for storing this but I cannot access it as a extender without violating the API and guessing at layouts which is kind of bad (Dan says so ;)
I don't know Perl5 internals enough to know exactly what Perl5LVALUE
does. Do you want a way to pass a value to the PMC and let the PMC type morph
itself based on the data representation?
-Melvin
An lvalue holds usually a function, and when set is called that function is called. So no morthing required at all!
For example:
perl -le '$foo = hi; $bar = \substr($foo,1); print "$bar-$foo"; $$bar = "b"; print "$bar-$foo"';
LVALUE(0x513ec)-hi
LVALUE(0x513ec)-hb
so the reference points to a lvalue which has a reference to $bar and a special function on the set to actually execute the substr.
The reason I am starting with this is that it is so obscure that it is hardly used anywhere and is limited to a few small areas in the core making it a good testing ground.
Arthur
