in reply to reference , advantages?

In new_date_append(), you are assigning a value to $monster_date, which is an undeclared variable, as far as I can see. Why aren't you getting an error message about that? That assigned value uses a global variable named $passed_new-date, which is not passed at all. The new value then becomes the return value of the routine.

$fref is assigned a reference to the subroutine, which might then be invoked as $fref->(); $$fref is meaningless and should generate an error.

As Occam said: Entia non sunt multiplicanda praeter necessitatem.

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Re^2: reference , advantages?
by Sandy (Curate) on Jun 30, 2011 at 18:00 UTC
    Actually, if you assume that the <snip> has the proper declarations, the $fref is a reference to the returned string from the function and $$fref is the string.

    Cleaned code 

    #!/usr/bin/perl
use strict;
use warnings;

my $passed_new_date = new_date();
my $fref = \&new_date_append();  ###--- HERE is my REF ---###

sub new_date {

 my ( $year, $month, $day ) = (localtime)[ 5, 4, 3 ];
 sprintf( "%04d%02d%02d", ( $year += 1900 ), $month + 1, $day );
}


sub new_date_append {
   return my $monster_date = "OhioS$passed_new_date";
}


if ( $passed_new_date and $$fref ) {
   print $$fref,"\n";
}

    [download]
    Result 
    >perl ref.pl
OhioS20110630

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