A couple of nice idioms come to mind. I'd code filter() as: 
sub filter {
    my $file = shift;

    local *FILE;
    open FILE, $file or die "Couldn't open: $file $!\n";

    while(<FILE>) {
        s/BASEURL=// and return qq|<li><a href="$_">$_</a></li>\n|;
    }
}

[download]
Even if that's too concise for you (localizing a glob automagically closes a filehandle when the glob goes out of scope, some people hate returning from within a loop, some people need to see an if there, though it deparses to the same thing), there's no need of doing a match and then a substitution. s/// has a return value for a reason. :) I do much prefer returning things than printing from within a function.

expand() could also be shorter: 

sub expand {
   map { bsd_glob($_) } @_;
}

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You'll need to call it as @ARGV = expand(@ARGV);, or just do it all in place.

Of course, we could end up with: 

print "<ul>\n", map { filter($_) } map { bsd_glob($_) } @ARGV, "\n";

[download]
It gets a little ridiculous, optimizing beyond that point. Still, you *could* do it that way.

In reply to Re: Pesky little URL files to HTML by chromatic
in thread Pesky little URL files to HTML by hsmyers

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