do, require, use, it doesn't matter — they all lead to an eval. If you don't want them, set up your own middle man to deal with the filesystem.

$ cat tt.pl 
sub foo { print "bar\n" }
$ cat ttmain.pl
package x;
eval `cat tt.pl`;
x::foo();
$ perl ttmain.pl 
bar
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Backticks and cat to prove the concept. Picking something robust to suit your needs is up to you.