Seems to work here, what version of perl are you using and how are you calling the sub? Here's a version abridged for the command line:

$ perl -Mstrict -we'{my %hsh;sub set:lvalue{$hsh{shift}}}my $baz=set("
+foo")="bar"; print $baz,$/,set("foo"),$/'
bar
bar
$

[download]
This is Perl 5.6.1.

Update: Changing the oneliner to be more like yours, I get:

$ perl -Mstrict -we'{my %hsh;sub set:lvalue{$hsh{shift}}}my $baz=set("
+foo")=([qw/bar baz/]); print $baz,$/,defined set("foo"),$/'
ARRAY(0x8106284)
1
$

[download]
which is what I'd expect. Recent AS should be fine.

U 2 : ++tadman for the solution, well spotted!

After Compline,
Zaxo

In reply to Re: lvalue subs return undef, playing with experimental features, the End of the World, etc by Zaxo
in thread lvalue subs return undef, playing with experimental features, the End of the World, etc by erikharrison

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