Re: return more than 1 value

[Utilitarian]

Hi changma_ha,

There are a few issues in your code, as pointed out above you can only return from a subroutine once so the second return is meaningless.

However if you return two arrays they are "flattened" and become indistinguishable. Take a look at the return documentation

As a result you should return references to the two arrays (or other data structure)

I have provided you with a code sample with comments which should make things clearer, play about with it and feel free to ask if you don't follow what it is doing.

use strict;
use warnings;


my @list =qw (1 2 3 4 5);
# define a hash to take back the values
my  %returned_values;
# get the array references
my ($keys, $values) = apackage::ahash(@list);
# Put them in a hash
@returned_values{@{$keys}} = @{$values};
# print out
for my $key (@{$keys}){
    print "$key maps to $returned_values{$key} \n";
}

package apackage;
sub ahash{
    my %hash;
# You are calling the subroutine with an uneven number of elements,
# You should check for this and correct before assigning to a hash
    if ((@_ % 2) != 0){
        push (@_,"null");
    }
    %hash = @_ ;
# Your foreach loop made no sense here
    my @ke = keys %hash;
    my @val = values %hash;
# return references to your two arrays
    return (\@ke, \@val);
# in this context returning a hash makes more sense
}

[changma_ha]

@ Utilitarian,i have another question regarding a line of your code. in @returned_values{@{$keys}} = @{$values}; how did u take a %returned_values as an array? i mean i am not getting this line properly. Thanks in advance

[Utilitarian]

@hash{@array_of_keys}=@array_of_values;
Is the Perlish way of assigning an array of values to their equivalent keys. You could, (if you enjoy typing), write

for my $index (0..$#array_of_keys){
   $hash{$array_of_keys[$index]}=$array_of_values[$index];
}

In the line you cite there isn't an array @returned_values it is a hash slice. take a look at the perldata man page for further, better presented, info

[changma_ha]

Thank you a lots Utilitarian....your example made my doubt clear..i will ask you..if i have any problems.