$ perl -V:sh
sh='cmd /x /c';

$ perl -e die(1)
1 at -e line 1.

$ perl -e " die(1) "
1 at -e line 1.

$ perl -e ' die(1) '
Can't find string terminator "'" anywhere before EOF at -e line 1.

$ perl -MO=Deparse,-p -e 'die(1)'
'???';
-e syntax OK

$ perl -MO=Deparse,-p -e "die(1)"
die(1);
-e syntax OK

$ perl -MO=Deparse,-p -e " system qw! perl -e warn(@ARGV) a r g v !"
system('perl', '-e', 'warn(@ARGV)', 'a', 'r', 'g', 'v');
-e syntax OK

$ perl -e " system qw! perl -e warn(@ARGV) a r g v !"
argv at -e line 1.