You're right about the floating numbers--it's never the case that one of the variables would be undefined. The use of "+0" is precisely the solution, but dare I say, an inelegant one. If I can say int $var1, I think there should be an equivalent counterpart for real numbers, as in real $var1 or float $var1.

Though the problem is solved, I'm still curious about the broader question of eval that I originally asked: is there a rule of thumb as to how inefficient it may be? Are there suggestions about when it's best to avoid it, and best to use it?

Dan Heller
http://www.danheller.com

In reply to Re^2: When is 'eval' too inefficient? by argv
in thread When is 'eval' too inefficient? by argv

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