No, if you declare $i inside the for loop the way marto has shown, the scope of $i will be only the for loop itself, not outside that block. Consider this example:

$ perl -E 'for( my $i=0; $i<10; $i++ ){say "Inside loop: $i";} say "Ou
+tside loop: $i";'
Inside loop: 0
Inside loop: 1
Inside loop: 2
Inside loop: 3
Inside loop: 4
Inside loop: 5
Inside loop: 6
Inside loop: 7
Inside loop: 8
Inside loop: 9
Outside loop:
[download]

You can see that the value of $i is not defined outside the loop. And if I add the warnings, I get:

...
Inside loop: 9
Use of uninitialized value $i in concatenation (.) or string at -e lin
+e 1.
Outside loop:
[download]