Bug #50656 for Scalar-List-Utils: Closure-friendly List::Util::reduce()

Mon Oct 19 13:40:34 2009 pollux [...] cpan.org - Ticket created

Subject:

Closure-friendly List::Util::reduce()

I would like to be able to do the following: my @f = ( sub { "a" }, sub { "b" }, sub { "c" }, sub { "d" }, sub { "e" }, ); my $f = reduce { sub { $a->() . $b->() } } ( sub { '' }, @f ); Of course, $f->() should return 'abcde'. Is there a way to do this currently or is it possible to modify reduce for this?

Mon Oct 19 14:44:46 2009 gbarr [...] pobox.com - Correspondence added

Subject:	Re: [rt.cpan.org #50656] Closure-friendly List::Util::reduce()
Date:	Mon, 19 Oct 2009 13:44:14 -0500
To:	bug-Scalar-List-Utils [...] rt.cpan.org
From:	Graham Barr <gbarr [...] pobox.com>

On Oct 19, 2009, at 12:40 PM, Paul Sandulescu via RT wrote: Show quoted text

> > I would like to be able to do the following: > > my @f = ( > sub { "a" }, > sub { "b" }, > sub { "c" }, > sub { "d" }, > sub { "e" }, > ); > > my $f = reduce { sub { $a->() . $b->() } } ( sub { '' }, @f ); > > Of course, $f->() should return 'abcde'.

nope. $a and $b are global and you are returning a sub so $a and $b are not resolved until the sub is run you could do my $f = reduce { my $c = $a->() . $b->(); sub { $c } } ( sub { '' }, @f ); which will cause $a->() and $b->() to be called during the reduce. Graham.

Mon Oct 19 14:44:46 2009 The RT System itself - Status changed from 'new' to 'open'

Sat Nov 14 09:53:48 2009 GBARR [...] CPAN.ORG - Status changed from 'open' to 'rejected'