my $DEBUG;
BEGIN {
   $DEBUG = $ARGV[0];
   if ($DEBUG) {
      eval <<'__EOI__';
         use strict;
         # <-- The compiler instance used
         #     by eval is here because
         #     Perl executes use statements
         #     as soon as it compiles them.
         #     "strict" will work until the
         #     end of this block (namely
         #     until the end of the code
         #     passed to eval).
__EOI__
   }
}
print($test);   # No strict error