Re: Known Bug in Rakudo?
On Thu, Oct 30, 2008 at 08:03:17AM -0700, Ovid wrote:
This code:
class Point {
has $.x is rw;
has $.y is rw;
method get_string () {
return $.x, $.y;
}
}
my Point $point .= new( :x1.2, :y-3.7 );
say $point.x;
say $point;
Generates this output:
1.2
get_string() not implemented in class 'Point'
Now fixed in r32373. The get_string() not implemented ...
message actually comes from Parrot -- in Perl 6 we define
stringification using the CStr method (see S13):
$ cat point.pl
class Point {
has $.x is rw;
has $.y is rw;
method Str() {
return $.x, $.y;
}
}
my Point $point .= new( :x1.2, :y-3.7 );
say $point.x;
say $point;
$ ./parrot perl6.pbc point.pl
1.2
1.2, -3.7
$
This problem was also addressed in RT #60350 (now resolved).
Hope this helps, and thanks!
Pm
Re: Known Bug in Rakudo?
Ovid wrote:
This code:
class Point {
has $.x is rw;
has $.y is rw;
method get_string () {
The correct way to define user-defined stringfication is either through
method Str { ... }
or
method prefix:~ ($self: ) { ... }
(afaict both are not implemented in Rakudo yet)
Parrots concept of 'get_string' is on a different level (vtable stuff I
think, but I don't grok the internals) and not accessible from Perl 6.
return $.x, $.y;
}
}
my Point $point .= new( :x1.2, :y-3.7 );
say $point.x;
say $point;
Generates this output:
1.2
get_string() not implemented in class 'Point'
I think that every class should have a default stringification. Dunno if
there's a ticket for it yet.
Cheers,
Moritz
--
Moritz Lenz
http://perlgeek.de/ | http://perl-6.de/ | http://sudokugarden.de/
Re: Known Bug in Rakudo?
On Thu, Oct 30, 2008 at 12:46 PM, Moritz Lenz
[EMAIL PROTECTED] wrote:
The correct way to define user-defined stringfication is either through
method Str { ... }
or
method prefix:~ ($self: ) { ... }
(afaict both are not implemented in Rakudo yet)
Yeah, I can't even declare a method that way (prefix:~), regardless
of whether or not Rakudo tries to call it to stringify. The $self:
isn't needed in this case, though, right? The body of the method just
uses $.x and $.y without going through a ref to the object.
As a point of comparison, Pugs accepts the operator overload
definition but doesn't honor it; ~$point still returns the generic
obj:Point.
--
Mark J. Reed [EMAIL PROTECTED]
Re: Known Bug in Rakudo?
On Thu, Oct 30, 2008 at 05:46:11PM +0100, Moritz Lenz wrote: I think that every class should have a default stringification. Dunno if there's a ticket for it yet. I don't think there's a _spec_ for a default stringification yet. So we should probably propose that first, and then see about an implementation. :-) Pm
Re: Known Bug in Rakudo?
Patrick R. Michaud wrote: On Thu, Oct 30, 2008 at 05:46:11PM +0100, Moritz Lenz wrote: I think that every class should have a default stringification. Dunno if there's a ticket for it yet. I don't think there's a _spec_ for a default stringification yet. So we should probably propose that first, and then see about an implementation. :-) $ perl5.10.0 -E 'say bless []' main=ARRAY(0x8c56880) If it's not specced in Perl 6, Perl 5 behaviour is used... Actually I think that the idea of printing a class name (or anon or something like that for anonymous classes) and a pointer address isn't all that bad, because it gives some basic information, and reminds the programmer that he either shouldn't print it, or define an overload method. A fatal error seem too strong to me... Anyway, a spec would still be nice. Moritz -- Moritz Lenz http://perlgeek.de/ | http://perl-6.de/ | http://sudokugarden.de/
