I re-kid you, Almut: eval, untainted, unrestricted??

Could you do a quick replace of <DATA> with <>, with piped input from find for me, and then permit me a run of a single perl -e. Just before you execute your script?

:>>

(ok, it's _DATA_ and thus controlled, but it still hurts on reading. And worse, that one is pure evil to both speakers of Perl and non-speakers alike)

Update: to restrict the hurt to mere aesthtics, consider this safer version of the input loop, which will also survive pasted arbitrary absolute pathes from DATA/or a switch from DATA to STDIN.

my @f=();                                    # PJ
while (<DATA>) {
    chomp;
s|([^/]+)|do{$f[$#f+1]=$1,'$f['.$#f.']'}|ge; # PJ
    s|^/|\$h->{|;
    s|/|}{|g;
s|$|} = 1;|;                                 # PJ
#print; print "\n";
    eval;
}
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food for thought

1. make 'tokenization' of filenames reuse 'tokens'
2. fix the loop to allow relative filenames (too trivial)
3. portability: also allow c:\data\no-such.fil
4. not a task, but an observation: use of Data::Dumper shows nicely the data structure of the recursive anonymous hash almut uses. This also demonstrates Perl's auto-vivication of the anonymous hashes we use hre: there's not one assignment of {}:
   $h->{$f[19]}{$f[20]}{$f[21]}{$f[22]} = 1;
5. a remark: normally you'd go for recursive functions when parsing a single path into a list of -> tree nodes. Or for a slightly less readable iterative 'unrolled' version of the same (keywords tail-recursion, loop-unrolling). The above code actually can be seen as such: everything but the s|/|}{|g; has been moved outside the loop, with the loop being reduced to just a looping regex substitution (/g modifier). Not much of a loop, not much for readability, and definitely not a sane nor a correct answer to give :)

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