Test for definedness of returned values because 0 is really { 0 => 1 } in our context

diff --git a/lib/Sub/Nary.pm b/lib/Sub/Nary.pm
index 14b882285723a2e3d20bbb7472c8502df1166d8a..52a3f8402e4c4783a0441da8ed35b24f4466ad9f 100644 (file)
--- a/lib/Sub/Nary.pm
+++ b/lib/Sub/Nary.pm
@@ -262,7 +262,7 @@ sub inspect {
 
   my $op = $op->first;
   my ($r1, $l1) = $self->inspect($op);
-  return $r1, $l1 if $r1 and zero $l1;
+  return $r1, $l1 if defined $r1 and zero $l1;
   my $c = count $l1;
 
   $op = $op->sibling;
@@ -551,11 +551,12 @@ sub pp_grepwhile {
  $op = $op->first->sibling;
 
  my ($r2, $l2) = $self->inspect($op->sibling);
- return $r2, $l2 if $r2 and zero $l2;
+ return $r2, $l2 if defined $r2 and zero $l2;
  my $c2 = count $l2; # First one to happen
 
  my ($r1, $l1) = $self->inspect($op);
- return (add $r2, scale $c2, $r1), undef if $r1 and zero $l1 and not zero $l2;
+ return (add $r2, scale $c2, $r1), undef if defined $r1 and zero $l1
+                                                        and not zero $l2;
  diag Dumper [ [ $r1, $l1 ], [ $r2, $l2 ] ] if $DEBUG;
  my $c1 = count $l1;
 
@@ -575,11 +576,12 @@ sub pp_mapwhile {
  $op = $op->first->sibling;
 
  my ($r2, $l2) = $self->inspect($op->sibling);
- return $r2, $l2 if $r2 and zero $l2;
+ return $r2, $l2 if defined $r2 and zero $l2;
  my $c2 = count $l2; # First one to happen
 
  my ($r1, $l1) = $self->inspect($op);
- return (add $r2, scale $c2, $r1), undef if $r1 and zero $l1 and not zero $l2;
+ return (add $r2, scale $c2, $r1), undef if defined $r1 and zero $l1
+                                                        and not zero $l2;
  diag Dumper [ [ $r1, $l1 ], [ $r2, $l2 ] ] if $DEBUG;
  my $c1 = count $l1;