[Parrot-users] A length() runtime written in NQP

[Jay Emerson]

I'm trying to write a function which would behave something like (pseudo-code):

a = 0
b = (1, 2, 3)
length(a)       # Returns 1
length(b)       # Returns 3

Now, in a squaak-like language, I think a is a scalar and b is a pmc.
I tried the following:

sub length(*@args) {
    my @arg := @args[0];
    my $len := @arg;
    pir::return($len);
}

Now, in interactive mode, length(b) seems to work (in terms of what is
printed), but the actual result
of length(b) seems to be the argument, b, itself.  So there is a print
generated which evaluates
@arg to the length (perl-like), but the actual thing returned is the
pmc.  I tried perl-like
$#arg to try to get the length, but that didn't work.

It would also be nice to know what causes the printing in squaak;

> a = 5
5
>

I'd like to "turn this off" and expect some modification to the
assignment method in Actions.pm is needed,
but don't see how to accomplish this.

Thanks,

Jay



-- 
John W. Emerson (Jay)
Associate Professor of Statistics
Department of Statistics
Yale University
http://www.stat.yale.edu/~jay