gube has asked for the wisdom of the Perl Monks concerning the following question:

Hi monks,

While, dereferencing and printing the reference array i am getting the exact values stored in the array. But, while dereferencing the array and printing by concatinate with some text i am getting length of the array do i need some changes in my code ?

#!/usr/local/bin/perl
use strict;
use warnings;
my @a = qw/a b c/;
my $a = \@a;
print @{$a}; # Printing correct output abc...
# It prints length of the array why?
print "Dereference and Printing the Reference array " . @{$a};

[download]

2006-04-26 Retitled by planetscape, as per Monastery guidelines
Original title: 'Dereferencing the array and printing by Concatinate?'

Replies are listed 'Best First'.
Re: Dereferencing the array and printing by Concatenation?
by gaal (Parson) on Apr 24, 2006 at 12:33 UTC
    This has nothing to do with references. 

    my @a = qw/a b c/;

print "Here are the elements. Notice the comma ", @a;
print "Here's the size. Notice the dot " . @a;

    [download]

    The concatenation operator "." puts the expression @a in scalar context. This also would print the size: 

    print "Notice the comma, but also 'scalar' ", scalar @a;

    [download]
[reply]
[d/l]
[select]

      Hi gaal,

      Thanks for your reply if i use comma it's working fine..This is nothing to do with reference <reply> I have used a long code, in that code while debug i have doubt so, i paste the small sample code...Thx..

[reply]
Re: Dereferencing the array and printing by Concatenation?
by TedPride (Priest) on Apr 24, 2006 at 12:45 UTC
    Actually, there's no need to use {} in this situation, since the reference is a simple variable, not something like @{$arr[0]}. You can just do @$ref. Also, as a matter of general policy, you don't want to use $a, since it's one of the variables Perl uses for sorting. 
    use strict;
use warnings;
my @x = qw/a b c/;
my $x = \@x;
print "Array elements with spaces: @$x";

    [download]
[reply]
[d/l]
[select]
Re: Dereferencing the array and printing by Concatenation?
by davorg (Chancellor) on Apr 24, 2006 at 12:43 UTC

    Or...

    print "Dereference and Printing the Reference array @{$a}";

    [download]

    That has the bonus of putting spaces (or whatever $" is set to) between the elements of your array.

    --
    <http://dave.org.uk>

    "The first rule of Perl club is you do not talk about Perl club."
    -- Chip Salzenberg

[reply]
[d/l]
Re: Dereferencing the array and printing by Concatenation?
by sen (Hermit) on Apr 24, 2006 at 12:35 UTC

    Hi gube try this

    print "Dereference and Printing the Reference array " , @{$a};

    [download]
[reply]
[d/l]

Back to Seekers of Perl Wisdom