Reversing array using array name and reference to array

Question

I have declared an array, and a reference to that array like this: -

my @array = (1, 2, 3, 4);
my $aref = \@array;

Now, I'm trying to reverse the array, using the array name and the reference name.

print reverse @array, "\n";
print reverse @{$aref}, "\n";

This is working fine, and printing the reversed array in both the cases: -

4321
4321

However, if I try to print the reverse in the same line, its giving me a strange result: -

print reverse @array, reverse @{$aref}, "\n";

Now, I got this output: -

1234
4321

and if I add a newline in between: -

print reverse @array, "\n", reverse @{$aref}, "\n";

I got this output: -

1234
4321

So, there are two problems as you can see: -

• 1st, The array is not getting reversed for using the name
• 2nd, there is an extra newline getting printed between the two reversed array.

I can't understand this behaviour, why this could be happening. Also I went through the documentation of the function reverse to check whether there is mentioned any where about this behaviour, but I didn't dine any. Can anyone explain what's happening here?

• Zaid: Running through perl -MO=Deparse ... helps you see what Perl is seeing more easily
• Rohit Jain: @Zaid. Thanks for the command. Still remaining to study about various commands. :)

Answer 1

reverse @digits, reverse @$digits, "\n"

means

reverse(@digits, reverse(@$digits, "\n"))

You want

reverse(@digits), reverse(@$digits), "\n"

or simply

reverse(@$digits, @digits), "\n"

• Rohit Jain: Oh man. I forgot the rule that parenthesis can be removed where it does not change the meaning. :( Thank you so much. :)
• Rohit Jain: Yeah It's working now. Will accept the answer once allowed. :)