I first realized this problem when I was checking to see if I had the latest version of Pod::HTML. Um, I mean, Pod::Html. The latter is included with the core Perl distribution, the former is part of the PodSimplify distribution. The problem is, the two are different modules, with different interfaces. If I had actually installed Pod::HTML, it would have overwritten Pod::Html, meaning that pod2html and any script that used Pod::Html would no longer work, and I would have a heck of a time figuring out why.

perlport says:

Do not have two files or directories of the same name with different case, like test.pl and Test.pl, as many platforms have case-insensitive (or at least case-forgiving) filenames.

Please note that this is not a flame against anyone who has written a module whose name differs from another module's by only case. It's difficult to take into account the peculiarities of other platforms when you're developing, especially when you can't test on those platforms.

(And yes, I am aware that there can be several different lib directories in which modules can be installed, but as long as one of them is always used for module installation, the problem with overwriting modules still applies.)

• Apache::Test | Apache::test
• base | Base
• Bio::Das::Request::dsn | Bio::Das::Request::Dsn
• Bio::SeqIO::EMBL | Bio::SeqIO::embl
• Bio::SeqIO::Fasta | Bio::SeqIO::fasta
• Bio::SeqIO::GCG | Bio::SeqIO::gcg
• Bio::SeqIO::Raw | Bio::SeqIO::raw
• Class::PObject::Driver::DB_File | Class::PObject::Driver::db_file
• Crypt::SecurID | Crypt::securid
• Crypt::TEA | Crypt::Tea
• DES | Des
• example | Example
• Example1 | example1
• FAQ::OMatic::Help | FAQ::OMatic::help
• FAQ::OMatic::Search | FAQ::OMatic::search
• File::Stat | File::stat
• Finance::Shares::Momentum | Finance::Shares::momentum
• Foo | FOO
• Gettext | gettext
• Graphics::PLPLOT | Graphics::PLplot
• Inline::CPP::Grammar | Inline::CPP::grammar
• LISP::List | Lisp::List
• LWP::Authen::Basic | LWP::Authen::basic
• LWP::Authen::Digest | LWP::Authen::digest
• Math::GSL | Math::Gsl
• Mcrypt | MCrypt
• MP3::Tag::ID3v1 | MP3::TAG::ID3v1
• MP3::Tag::ID3v2 | MP3::TAG::ID3v2
• My::db | My::DB
• Net::LDAP::Control::Sort | Net::LDAP::Control::sort
• Net::TrackBack | Net::Trackback
• Petal::Hash::VAR | Petal::Hash::Var
• Pod::HTML | Pod::Html
• Pod::Rtf | Pod::RTF
• pragmatic | Pragmatic
• Qt | QT
• SGI::syssgi | SGI::Syssgi
• stem | Stem
• swig | SWIG
• Sys::Lastlog | SYS::lastlog
• testcases::Base | testcases::base
• types | Types
• URI | uri
• XBase | Xbase

#!/usr/bin/perl -w
use strict;

#File below is decompressed http://perl.org/CPAN/modules/02packages.de
+tails.txt.gz
open(MODULES, '<', '02packages.details.txt') or die "Can't open module
+ info: $!";
my %all_modules;
my %duplicates;


my $inheader = 1; #02packages.details.txt has several header lines, th
+en a blank line, then the module names.
while (<MODULES>)
{
    if ($inheader) #This technique for ignoring the header was taken f
+rom
    {                            #Merlyn's MINICPAN script: http://www
+.stonehenge.com/merlyn/LinuxMag/col42.html
        $inheader = 0 unless /\S/;
        next;
    }

    my ($module, undef, undef ) = split;
    
    if(exists $all_modules{lc $module})
    {
        push @{$all_modules{lc $module}}, $module;
        $duplicates{lc $module} = 1;
    }
    else
    {
        $all_modules{lc $module} = [$module];
    }
}

print scalar(keys %duplicates)." sets of duplicates:\n\n";

foreach(sort keys %duplicates)
{
    print join ' | ', @{$all_modules{$_}};
    print "\n";
}
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