Yeah sure, I agree that eval is always potentially
dangerous... I figured this is rather well-known. And, I wasn't trying
to spread "great memes" :) Rather, I was simply trying to
generically answer the problem of "Normally, I would use a double
quoted string in my script... now what do I do to arrive at the same
effect when I hold the part in between the quotes literally in a
string, like when having read it from a file?" Nowhere in the OP
was any mention of other people potentially having control over the input.
Along similar lines you'd have to warn people every time they
interpolate some variable into some command like
system "convert $imgname.png $imgname.jpg"
because, if $imgname could potentially come from an insecure
source, they might get into trouble inadvertendly running something like
system "convert ; rm -rf ~/* ;.png ..."
I'd probably even mention it if the danger is obvious, like someone
inexperienced trying to execute code like this in CGI context or some
such, but otherwise... should we always warn?
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