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"; }
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"; }
In reply to 2d arrays and 'Can't use string as an ARRAY ref' by ronlewis
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