in reply to Re^2: Entering the land of Perl
in thread Entering the land of Perl
Hi manbroski,
"..Notice that I have to dereference it after the passage.." Why is that?
Did you also notice your subroutine sort_and_print_hash_keys definition
and how you eventually used the it like so:sub sort_and_print_hash_keys (\%) {..
".. But as far as the prototype passing, I was certain that it enforces a pass by reference..."sort_and_print_hash_keys(%letters); # you passed a hash variable not a + hash ref.
If I may suggest, you will do well yielding the wisdom of jwkrahn, as regard the usage of prototype for this reason:
When you use a reference prototype, like "\$", "\@", "\%" "...those symbols don't actually say that you must pass in a scalar reference, an array reference, and a hash reference. Rather, they say you must pass in a scalar variable, an array variable, and a hash variable. That means that the compiler insists upon seeing a properly notated variable of the given type, complete with "$", "@", or "%" in that slot. You must not use a backslash. The compiler silently supplies the backslash for you... "
from Far More than Everything You've Ever Wanted to Know about Prototypes in Perl -- by Tom Christiansen
-- by liverpole, under subheading Problems with Reference Prototypes
Hope this helps.
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me
|
---|
In Section
Seekers of Perl Wisdom