sub wa {
    my $place = shift @_;
    my $context = wantarray ? 'list'
                : defined wantarray ? 'scalar' : 'void';
    warn "'$context' context at '$place'\n";
}

my $x ||= (wa('oe1'),wa('oe2'),wa('oe3'));
print "\n";
my $y = (wa('e1'),wa('e2'),wa('e3'));
print "\n";
my $z = sub { (wa('s1'),wa('s2'),wa('s3')) }->();
__END__
'void' context at 'oe1'
'void' context at 'oe2'
'scalar' context at 'oe3'

'void' context at 'e1'
'void' context at 'e2'
'scalar' context at 'e3'

'scalar' context at 's1'
'scalar' context at 's2'
'scalar' context at 's3'