I wanted to make a point. Show what Perl does when you feed it code, by writing code that writes code and feeds it back to Perl, as if it were written by you :) . Of course, the obvious solution is to just take away recursion from broquaint's version: 

sub flatten { map { ref $_ eq 'ARRAY' ? @$_ : $_ } @_ }

[download]

This is an extremely scary solution. So scary that I can only assume you are joking. Please dont suggest things like this without a security disclaimer. A fresh newbie might think its a good plan then end up having their hard drive deleted or other nasty tings.

This sounds freaky. I'm curious, can you post an exploit against flatten_stringeval?. The only thing interpolated is $_, which iterates through (0..$#_). Everything else is quoted. Also, it checks for hard array ref before putting @{...}, so one can't play games with symbolic references (one doesn't need string eval for that, just no strict 'refs'). Maybe I'm missing something...

In reply to Re: Re: Re: flattening a list-of-lists by calin
in thread flattening a list-of-lists by Anonymous Monk

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