What if with "dangerous languages" like C you could turn off pointers, or make only functional subroutines?

For instance, perl has this construct, to make your programs better:

a program foo.pl:

  $c = 1;

runs fine. Now turn on strict:

  use strict;
  $c = 1;

and

  $ perl ./foo.pl 
  Global symbol "$c" requires explicit package name at ./foo.pl line 2.
  Execution of ./foo.pl aborted due to compilation errors.

you must declare $c:

  my $c = 1;

the idea would be... write your program and you can opt-in to various constructs.

NOTE: my first example didnt' work.

  use strict;
  $a = 1;

won't throw an error. Turns out the variables "$a" and "$b" are exempt from "use strict;" ha. wow.