I ran into a problem trying to convert Leo's "Case 1" example so that it
uses methods instead of subs. Here's how far I got:
.HLL 'Amber', 'amber_kernel'
.sub main :main
newclass $P0, 'FOO'
$P1 = new 'FOO'
$P1.main()
.end
.namespace [ "FOO" ]
.sub main :method
$P0 = self.do_add3(20)
print $P0
print "\n"
.end
.sub do_add3 :method
.param pmc arg
.const .Sub add3sub = 'add3' #(1)
.local pmc add3closure
add3closure = newclosure add3sub
#$P1 = self.add3sub(arg) #(2)
$P1 = self.add3closure(arg) #(3)
.return ($P1)
.end
.sub add3 :method :outer('do_add3') #(4)
.param pmc arg
$P0 = n_add arg, 3 #(5)
.return($P0)
.end
This segfaults at #(3). Possibly, I need to specify the FOO namespace at
#(1) and/or #(4). But how? It doesn't work to write 'FOO\0add3', for
example.
Now for the really strange thing: I can make this example work by doing
any one of several apparently-unrelated things:
- uncomment line #(2)
- remove the ":outer('do_add3')" part of line #(4)
- remove the .HLL declaration at the top of the program
- replace line #(5) by "$P0 = n_neg arg" (the significance
of this might be that 'n_neg' is redefined in the
Amber_INTEGER PMC - other operations are inherited
unchanged from the Integer PMC)
Does anyone have any ideas where I can look for clues?
Regards,
Roger Browne
Here's Leo's original example:
> .pragma n_operators 1 # add creates new PMC result below
> .sub do_add3
> .param pmc arg # looks nicer than get_params
> .lex '$a', arg
> .lex '&add3', $P1
> .const .Sub add3 = "add3"
> $P1 = newclosure add3
> $P2 = $P1() # tailcall eventually - b0rked
> .return ($P2)
> .end
>
> .sub add3 :anon :outer(do_add3) :lex
> $P0 = find_lex '$a'
> $P1 = $P0 + 3 # create/return new value
> .return ($P1)
> .end
>
> .sub main :main
> $P0 = do_add3(20)
> print $P0
> print "\n"
> $P1 = do_add3(21)
> print $P1
> print "\n"
> .end
>
