Unbalanced `if-else` Blocks

Returning to the each_file example of three slides ago:

        sub each_file {
          return unless -T $_;

          if ( open F, "< $_" ) {
            my $s = <F>; 
            close F;
            if ( open F, "> $_" ) { 
              $s =~ s/COLUMN1/COLUMN1/ig;
              print F $s;                
              close F;
            }
            else {
              print "Error opening file for write: $!\n";
            }
          }
          else {
            print "Error opening file for read: $!\n";
          }
        }

These if blocks are all quite top-heavy
The normal flow of the function is 1-2 levels deep
- (2-3 before we banished the Condition that Ate Michigan)
Normal flow should be close to the margin
It's hard to see which else goes with which if

Unbalanced if-else Blocks

Unbalanced `if-else` Blocks