You want to buy The Damian == 'Damian Conway' book on Object Oriented Perl - Google for same. Damian is a Perl guru and comes from C++ Here is short closure example of a private var, and private func: 

# here $count and $private_func are undef
# add_to_count() sub_from_count() get_count() set_count() and widget()
# are the only ways to access $count and ($)private_func()

{
    # use a closure to keep peoples sticky fingers off $count
    my $count;

    # define a func totally private to this closure
    my $private_func = sub { [blah blah blah] }

    # now here are a couple of modifiers
    sub add_to_count { 
        ++$count 
    }
    sub sub_from_count { 
        --$count 
    }

    # and the usual couple of accessors....
    sub get_count { 
        $count 
    }
    sub set_count {
        my ($new_count, $user ) = @_;
        if ( $user = 'root' ) {    # OK, OK so it is a silly example!
            $count = $new_count;
          return $count;
        }
        else {
            warn "Only root can set count directly, use add/sub/get bl
+ah..."
          return undef;
        }
    }

    # and something silly to use our private func...
    sub widget {
        &$private_func(@_) if $moon_in_venus && $believe_that_sort of 
+stuff;
    }
}

# here $count and $private_func are undef

[download]

This shows you how to make a private var and use it but you can make private funcs as well using the syntax shown. Only stuff in the closure (block) can use it using syntax &$privat_func(@args). Note a perl func returns the last val evaluated so you can often neglect the return as it is imlicit.

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: characterstics of private in perl by tachyon
in thread characterstics of private in perl by Anonymous Monk

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