>perl -wMstrict -le
"my $str = 'a|  b||c  |  0  ';
 ;;
 $_ //= ''
   for my ($var1, $var2, $var3, $var4, $var5, $var6) =
     map Trim($_), split m{\|}xms, $str;
 ;;
 printf qq{'$_'  } for $var1, $var2, $var3, $var4, $var5, $var6;
 ;;
 sub Trim {
   $_[0] =~ s{ \A \s+ | \s+ \z }''xmsg;
   return $_[0];
   }
"
'a'  'b'  ''  'c'  '0'  ''