How about returning an iterator in scalar context? For example, XML::XPath (and a lot of the XML::* modules for that matter) has a method findnodes() that returns such: 
if ($results->isa('XML::XPath::NodeSet')) {
   return wantarray ? $results->get_nodelist : $results;
#  return $results->get_nodelist;
}

[download]
The docs for Tie::Array::Iterable need some corrections, and you don't actually do the tieing ... but here is an example with it: 
#!/usr/bin/perl -l

use strict;
use warnings;
use Tie::Array::Iterable;

sub foo {
   my @list = 0..9;
   return wantarray ? @list : Tie::Array::Iterable->new(@list);
}

# access as a list
print for foo();

# or an iterator
my $iter = foo()->from_start();
print ($iter->value),$iter->next until $iter->at_end;

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to Re: What should be returned in scalar context? by jeffa
in thread What should be returned in scalar context? by tilly

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