Ah, I missed the side-effect of the function, sorry. In fairness, Perl has no way of knowing (as I should have from the name of the function, "log") that your function has a side-effect. If this function were to simply return a value, then the warning would make sense, because you would be storing a value and never using it. With the side-effect, though, everything becomes clear.

If you really want that syntax, then you should turn warnings off as others have suggested. Alternatively, you could use a syntax which mentions the variable twice. I don't know if the fact that I missed the meaning of your code is indicative of unclear syntax, or if it's just me being blind this morning.

In reply to Re^3: Why do I get a "used only once" warning here? by bellaire
in thread Why do I get a "used only once" warning here? by rovf

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