Timo,
One can even pass hash to a subroutine with a little trick, 'cos the default
argument of a subroutine is an array "@_". ** Check Example 2, in the code
below.
I think this trick is formalized by context rule.
@voo = ("boon", 12, "man", 88);
%coo = @voo;
my $line = "";
while(my ($key, $val) = each %coo){
$line.="$key => $val\n";
}
print $line;
On Sat, Jul 30, 2011 at 2:17 AM, timothy adigun <2teezp...@gmail.com> wrote:
> Hi Rajeev,
> with the link you provided, the statement "In Perl, you can pass only one
> kind of argument to a subroutine: a scalar... a pointer (sort of)." was
> made
> Reference sub-topic. So, it will not be a total truth that one can pass
> "only" one kind of argument to subroutine.
> Generally in perl the subroutrine default argument is an array "@_", so
> that
> makes it possible to even pass arrays into subroutine! ** Check Example 1,
> in the code below.
> One can even pass hash to a subroutine with a little trick, 'cos the
> default
> argument of a subroutine is an array "@_". ** Check Example 2, in the code
> below.
> Finally, I believe that "one" the main purpose of reference in perl is to
> help maintain the integrity of data passed to a subroutine.
> In Code Example 3 below, two arrays were passed to a sub., inside the sub.
> the two array merges to one, and lost identity, then printer with just one
> for loop.
> But one can keep these array intact, using reference as demonstrated in **
> Code Example 4!
> To write Object oriented perl one might have to know reference well! Really
> it like pointer or passing reference using pointer in c++.
>
> <CODES>
>
> #!/usr/bin/perl -w
> use strict;
>
> ##Example 1#################
>
> sub getter(@); #declaration of subroutine
>
> my $list="";
> my @arr=qw( 12 timo kunle 067 23.90 come_hm);
>
> sub getter(@){ # defination of subroutine
> foreach(@_){
> $list.="$_\n";
> }return $list;
> }
>
> print getter(@arr); # print return value
>
> ##################################################################
> ##Example 2#################
>
> my %hash=( fistname=>'larry', surname=>'wall',
> street=>'earth', value =>'perl');
>
> my $line="";
> sub getter_hash{
> my %hash=@_; # the trick convert ur @_ to %hash
> while(my ($key,$val)=each %hash){
> $line.="$key => $val\n";
> }
> return $line;
> }
>
> print getter_hash(%hash);
>
> ###################################################################
> ##Example 3#################
>
> sub getter3(@); #declaration of subroutine
>
> $list="";
> my @arr1=qw( 12 timo kunle 067 23.90 come_hm);
> my @arr2=qw( US 23:46:13 local float GOP_DEBT -q34A);
>
> sub getter3(@){ # defination of subroutine
> foreach(@_){
> $list.="$_\n";
> }return $list;
> }
>
> print getter(@arr1,@arr2); # print return value
>
> #################################################################
> ##Example 4#################
>
> sub getter4($$); #declaration of subroutine
>
> my $count=0;
> my @arr3=qw( 12 timo kunle 067 23.90 come_hm);
> my @arr4=qw( US 23:46:13 local float GOP_DEBT -q34A);
>
> sub getter4($$){ # defination of subroutine
> my ($val1,$val2)=@_;
> foreach(@{$val1}){++$count;
> print "$count:$_\n";
> } $count=0;
> foreach(@{$val2}){++$count;
> print "$count:$_\n";
> }
> }
> getter4(\@arr3,\@arr4); # print return value
>
> Regards.
>
>
>
>
> On Fri, Jul 29, 2011 at 11:57 PM, Rajeev Prasad <rp.ne...@yahoo.com>
> wrote:
>
> > Hello,
> >
> > from here: http://www.troubleshooters.com/codecorn/littperl/perlsub.htm
> >
> > i found:
> >
> > In Perl, you can pass only one kind of argument to a subroutine: a
> scalar.
> > To pass any other kind of argument, you need to convert it to a scalar.
> You
> > do that by passing a reference to it. A reference to anything is a
> > scalar. If you're a C programmer you can think of a reference as a
> pointer
> > (sort of).
> >
> > is that still true? date on website is 2003...
> >
> > thank you.
> >
> > Rajeev
> >
>
--
*Satajanus Nig. Ltd
*
