After tearing my hair out the whole day, it's time to seek some wisdom.

I'm trying to manipulate scalars in a 2-dimensional array.

For example, I might want do a substr() operation on each scalar. I can't do it without seeing strange error messages which I don't understand.

I understand the principle of Perl's 2-dimensional arrays as a list of references to lists. However, these error messages make no sense to me. Could someone nudge me in the right direction?

#! /usr/bin/perl -w

use strict;
use warnings;

# Create a one-dimensional array
my @row = ('a sheep', 'an elephant', 'the wolf');

# Use it as the first row in a 2-dimensional array
my @twoDimArray = (\@row);

# List of articles in the English language
my @articleList = ('the', 'a', 'an');

# Remove articles from animals
OUTER: foreach my $animal ($twoDimArray[0]) {
    INNER: foreach my $article (@articleList) {
                
        if (index ($animal, $article) == 0) {
            # Article found at beginning of $animal. Remove it.
            $animal = substr($animal, (length($article) + 1));
            # Only need to remove one article from each animal
            last INNER;
        }
    }
}

# Print a list of three animals
# I expect to see the output
#    Animal:     sheep
#    Animal:    elephant
#    Animal:    wolf
# Why do I get only get one animal, and an array reference?
#    Animal: ARRAY(0x8343218) 
foreach my $animal ($twoDimArray[0]) {
    print "Animal: $animal\n";
}
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I tried another approach, and got a different strange error message.

#! /usr/bin/perl -w

use strict;
use warnings;

# Create a one-dimensional array
my @row = ('a sheep', 'an elephant', 'the wolf');

# Use it as the first row in a 2-dimensional array
my @twoDimArray = (\@row);

# List of articles in the English language
my @articleList = ('the', 'a', 'an');

# This code block produces the error
#    "Can't use string ("RAY(0x8641210)") as an ARRAY ref while "stric
+t refs" in use at ./arraytest.pl line 22."
#
# Remove articles from animals
OUTER: for (my $count = 0; $count < 3;$count++) {
    INNER: foreach my $article (@articleList) {
                
        if (index ($twoDimArray[0][$count], $article) == 0) {
            # Article found at beginning of $animal. Remove it.
            $twoDimArray[0] = substr($twoDimArray[0], (length($article
+) + 1));
            # Only need to remove one article from each animal
            last INNER;
        }
    }
}

# Print a list of animals
foreach my $animal ($twoDimArray[0]) {
    print "Animal: $animal\n";
}
[download]