use is really the following code: 
use My::Module @args;

# This becomes ...

BEGIN {
    require My::Module;
    My::Module->import( @args );
}

[download]

require is approximately the following code: 

require My::Module;

# This becomes ...

sub require {
    my ($name) = @_;

    (my $filename = $name) =~ s!::!/!g;
    $filename .= '.pm' if $name =~ /::/;

    unless ( exists $INC{ $filename } ) {
        # Load the file into memory, figuring out which of @INC to use
+.
        # Put the full pathname into $full_path_name
        $INC{ $filename } = $full_path_name;
    }
}

[download]

So, if a module has already been loaded, it won't be loaded again, but its import() will be called again (as tye noted in the original thread).

Your confusion is arising because you're attempting to load File::BaseName and File::Basename on case-insensitive operating system. Because it's case-insensitive, the check against %INC is subverted. On case-insensitive operating systems, the following version of require may be more appropriate: 

sub require {
    my ($name) = @_;

########## THIS IS ADDED
    $name = lc $name;
########## TO HERE

    (my $filename = $name) =~ s!::!/!g;
    $filename .= '.pm' if $name =~ /::/;

    unless ( exists $INC{ $filename } ) {
        # Load the file into memory, figuring out which of @INC to use
+.
        # Put the full pathname into $full_path_name
        $INC{ $filename } = $full_path_name;
    }
}

[download]

That should appropriately fix things. (But, it won't catch things like use Strict; - that lc fix would have to be part of use, which may not be a bad thing.)

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Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re: What happens when you load the same module twice? by dragonchild
in thread What happens when you load the same module twice? by periapt

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