The intent behind only used once warnings is that it may be a mistyped variable - for instance, you might have a $variable in your code which somewhere is referred to as $vairable. This warning would catch it (however it seems a bit pointless to be warned of single-use variables when at the same type strict will force an error at compile time on mistyped variable names).

In reply to Re^3: Good programming practice by Aristotle
in thread Good programming practice by Purdy

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