Add "use diagnostics;" to the top of your script and run it again. You'll see a more thorough explanation, including this:

Although defined %hash is false on a plain not-yet-used hash, it becomes true in several non-obvious circumstances, including iterators, weak references, stash names, even remaining true after undef %hash. These things make defined %hash fairly useless in practice. If a check for non-empty is what you wanted then just put it in boolean context (see "Scalar values" in perldata): 

    
        if (%hash) {
           # not empty
        }

[download]

There's not much I can add to that, other than to say that by following the advice above you may actually be removing an undiscovered bug.


Dave

In reply to Re: Code cleanup; how best to deal with: defined(%hash) is deprecated at... by davido
in thread Code cleanup; how best to deal with: defined(%hash) is deprecated at... by taint

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