Re: Introspection and list question
On Wed, Dec 13, 2006 at 10:55:28AM +0200, Gaal Yahas wrote:
: L stipulates the
: results of a gather are flattened to a lazy list. I'm not sure how far
: that flattenning goes, but one of these should do the trick, I think
It would only flatten a recursive structure with the help of something
that recurses. The flattening of gather/take itself is only one level,
insofar as the various takes are treated as "pushes" onto the list
being gathered.
: (Pugs does not yet implement gather/take):
Actually, it does, but only the block form. The generalization to any
statement (using C syntax) was a very recent change.
The following prints (1, 2, 3, 4, 5) in current pugs:
#!/usr/bin/pugs
my $a = [1,2,[3,4],5];
multi flattener ($x) {
take $x;
}
multi flattener (Array @array) {
for @array -> $elem {
flattener($elem);
}
}
sub flatten ([EMAIL PROTECTED]) {
for @args -> $arg {
return gather { flattener($arg) }
}
}
$a.flatten.perl.say;
Larry
Re: Introspection and list question
On Tue, Dec 12, 2006 at 02:19:46PM -0800, Ovid wrote:
> First, how do I do introspection in Pugs? CPAN's Perl6::Bible hasn't
> been updated in a while, but the various ways to get a list of methods
> (from
> http://search.cpan.org/dist/Perl6-Bible/lib/Perl6/Bible/S12.pod#Introspection
> or http://tinyurl.com/yxukar) don't appear to work. They all throw
> syntax errors or "No compatible subroutine" errors.
In general you're better off looking at http://spec.pugscode.org/ for
more updated synopses, but in regard to introspection, the APIs aren't
well specced yet.
> Also, I'm having trouble with problem 7 in
> http://www.ic.unicamp.br/~meidanis/courses/mc336/2006s2/funcional/L-99_Ninety-Nine_Lisp_Problems.html
> or http://tinyurl.com/tt9e7. Basically, it's flattening nested lists
> and I'm embarrassed to admit that I can't figure this out in Perl6.
> Thoughts? I've been reading synopses and grepping through Pugs, but to
> no avail.
L stipulates the
results of a gather are flattened to a lazy list. I'm not sure how far
that flattenning goes, but one of these should do the trick, I think
(Pugs does not yet implement gather/take):
sub flatten1 (@list) {
gather for @list {
take $_;
}
}
sub flatten2 (@list) {
gather for @list {
take $_.does("List") ?? flatten2 $_ !! $_;
}
}
--
Gaal Yahas <[EMAIL PROTECTED]>
http://gaal.livejournal.com/
Re: Introspection and list question
On 12/12/06, Ovid <[EMAIL PROTECTED]> wrote: Hi all, A couple of quick things. First, how do I do introspection in Pugs? CPAN's Perl6::Bible hasn't been updated in a while, but the various ways to get a list of methods (from http://search.cpan.org/dist/Perl6-Bible/lib/Perl6/Bible/S12.pod#Introspection or http://tinyurl.com/yxukar) don't appear to work. They all throw syntax errors or "No compatible subroutine" errors. it seems much of this is unimplemented. from the pugs test dir, C returns some tests, but most of them are decorated with C<< :todo >>. Also, I'm having trouble with problem 7 in http://www.ic.unicamp.br/~meidanis/courses/mc336/2006s2/funcional/L-99_Ninety-Nine_Lisp_Problems.html or http://tinyurl.com/tt9e7. Basically, it's flattening nested lists and I'm embarrassed to admit that I can't figure this out in Perl6. Thoughts? I've been reading synopses and grepping through Pugs, but to no avail. * in index position flattens an array. it's mentioned in S02 (http://dev.perl.org/perl6/doc/design/syn/S02.html), among other places. a quick test at http://run.pugscode.org/ suggests that it works, too: pugs> my @a=[1,2,[3,4],5]; say @a[*]; 1 2 3 4 5 ~jerry
