Hi Monks!
I'm trying to get the canonical path of a given path (without '.', '~', '..', ... - just the unique path, string with '/'). I came across with this question and solution. The suggested code: 
foreach my $path ("/a/b/c/d/../../../e" , "/a/../b/./c//d") {
    my @c= reverse split m@/@, $path;
    my @c_new;
    while (@c) {
        my $component= shift @c;
        next unless length($component);
        if ($component eq ".") { next; }
        if ($component eq "..") { 
            my $i=0;
            while ($c[$i] =~ m/^\.{0,2}$/) {
                $i++
            }
            splice(@c, $i, 1);
            next 
        }
        push @c_new, $component;
    }
    print "/".join("/", reverse @c_new) ."\n";
}

[download]
It works good for most cases but I had trouble with paths that start, for example, with ".." (like "../script.sh") then it gives me: Use of uninitialized value within @c in pattern match (m//).
How can it possible to fix this code to support those cases?
Please note that I don't want to get the absolute path of the given path - meaning, I don't want to resolve any links on the way. Just to get the canonical path of the given path - starting from root, without '..', '.', '~' symbols. For example, given "../softlink/script.sh" where softlink is a link to some other area "softlink -> /a/b/c" then I want to get: "/root/to/that/path/softlink/script.sh" (I didn't resolve the link)

In reply to How to get the unique canonical path of a given path? by ovedpo15

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