Consider the following line of code:

$value += $var1 || $var2;

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This doesn't work if $var1 is 0.00, because perl doesn't evaluate it as a number, but as a string. To get it to work, I have to do:

$value += eval $var1 || eval $var2;

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This works now, but it's inside a very long loop. Should I regard eval as expensive and use it sparingly, only when I really need it? Are there rules of thumb as to when eval is efficient and when it's wasteful?

Dan Heller
http://www.danheller.com

In reply to When is 'eval' too inefficient? by argv

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