As I already said, you could tie the variable with a self-made STORE (
+This, Value) function which does your checks on Value before storing 
+it.

[download]

allow me to clarify the above, in reference to what you said before that: 

You could use Tie::Scalar to make sure that a var $x will always stay 
+an integer, by declaring STORE. But that will slow down every operati
+on on $x.

[download]
, just use the slow Tie::Scalar to only do the validation, then store the validated integer into a "normal" variable.

In reply to Re^4: way of declare an integer variable instead use /^\d+$/ by bliako
in thread way of declare an integer variable instead use /^\d+$/ by vincentaxhe

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