If you want a number force numeric conversion. 

$ perl -le '$var1 = "0.00"; $value += ($var1+0) || 99; print $value' 
99

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And your use of eval there is string eval so yes that's expensive and not really a good idea.

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

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