I just spent some time debugging a problem which turned out to be due to
the "set" operator not doing what I expected (i.e., calling pmc_set).
In retrospect, what set id doing is perfectly defensible, but "setref",
as implemented by PerlScalar, remains counter intuitive, at least to me:
.sub main @MAIN
set $P1, $P0
setref $P2, $P0
print "$P1 = "
print "$P2 = "
- Sam Ruby