c:\@Work\Perl\monks>perl -wMstrict -le
"print qq{perl array base is $[};
 ;;
 my @ra = ();
 print qq{A: array (@ra) is empty} if $#ra + 1 - $[ == 0;
 ;;
 @ra = (1);
 print qq{B: array (@ra) is empty} if $#ra + 1 - $[ == 0;
"
perl array base is 0
A: array () is empty

c:\@Work\Perl\monks>perl -wMstrict -le
"$[ = 1;
 print qq{perl array base is $[};
 ;;
 my @ra = ();
 print qq{A: array (@ra) is empty} if $#ra + 1 - $[ == 0;
 ;;
 @ra = (1);
 print qq{B: array (@ra) is empty} if $#ra + 1 - $[ == 0;
"
Use of assignment to $[ is deprecated at -e line 1.
perl array base is 1
A: array () is empty