I am starting to learn Perl by reading "Learning Perl" and testing on a Centos box.

I typed in a piece of code from the book and it did exactly what the book said it should do... But I don't know why!

This is the code I typed in (modded to my coding requirements):

use strict;
use warnings;
my @lArray;
my @lNums = 1..3;
unshift @lArray, 5; print "Array: @lArray\n";
unshift @lArray, 4; print "Array: @lArray\n";
unshift @lArray, @lNums; print "Array: @lArray\n";

[download]

The output of the third print is "Array: 1 2 3 4 5", exactly as the book showed. My question is why is it that way? After thinking about it my expectation was that it would be "Array: 3 2 1 4 5".

I expected "unshift @lArray, @lNums" to expand to "unshift @lArray, 1 2 3" and then be processed as though:

unshift @lArray, 1
unshift @lArray, 2
unshift @lArray, 3

[download]

However, it doesn't. It looks like the unshift operation is processing the values given in reverse order (3 2 1). Is this true? If not, how is it putting them in in the given order rather than reversed?

Anyway, that's my problem; totally confused by Chapter 3.

In reply to I am confused by a "Learning Perl" sample showing "unshift" by KenAndrews

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