in reply to Case insensitivity in a hash... Futile effort?

Well, first of all, redefining the hash *would* get rid of Apple => red, but that's probably not what you meant. :)

In a thread a while back, vroom wrote a nice solution using tie: Re: case sensitivity in hashes.

You'll have to modify it a bit, because you want multi- dimensional hashes; so I think you'd probably just have to tie all of the hashes of hashes of hashes, etc. So, for example, say you're using vroom's Tie::CaseInsensitive: 

use strict;

my %HASH;

use Tie::CaseInsensitive;
tie %HASH, 'Tie::CaseInsensitive';

$HASH{BoB}  = 1; 
$HASH{bob}  = 2;
$HASH{BOb}  = 3;

tie %{$HASH{bill}}, 'Tie::CaseInsensitive';
$HASH{bill}{jones} = 3;
$HASH{BILL}{JONES} = 2;

use Data::Dumper;
print Dumper \%HASH;

[download]
You should get: 
$VAR1 = {
          'bill' => {
                      'jones' => 2
                    },
          'bob' => 3
        };

[download]
which looks quite right.

Replies are listed 'Best First'.
RE: Re: Case insensitivity in a hash... Futile effort?
by ChuckularOne (Prior) on Apr 19, 2000 at 00:37 UTC
    So to tie a hash four dimensional hash, I would: 
    $level1 = "LEVEL1";
$level2 = "LEVEL2";
$level3 = "LEVEL3";

$setting1 = "level1";
$setting2 = "level2";
$setting3 = "level3";

use Tie::CaseInsensitive;
tie %{$HASH{$level1}{$level2}{level3}}, 'Tie::CaseInsensitive';

$HASH{$level1}{$level2}{level3} = 3;
$HASH{$setting1}{$setting2}{setting3} = "Three";

use Data::Dumper;
print Dumper \%HASH;

    [download]
    I tried to run this code and got the following error:
    Can't locate Tie/CaseInsensitive.pm in @INC at ./hashTieTest.pl line 12.
    I'm guessing this means that I need to add a .pm .
    but which one? Is there a tie.pm? I'll go check CPAN. -Chuck
[reply]
[d/l]
      Tie::CaseInsensitive can be gotten here: Re: case sensitivity in hashes.

      Just copy and paste it into your editor, save it, then put it somewhere in your @INC as Tie/CaseInsensitive.pm.

      And w/ a multi-dimensional hash, you need to tie each level of the hash. Does that make sense? So you tie the hash %HASH, then you tie $HASH{level1}, and so on down.

[reply]
        I hate sounding ignorant, but once I know what I'm doing I promise to answer questions rather than just ask them.

        How do I add something to @INC. All my books are at work and I'm trying to get this done.

        Your humble servant,
        -Chuck
[reply]
        Thanks a lot, It makes sense, but I don't think I'd have figured it out :-)
        -Chuck
[reply]

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