This doesn't work in your example, where you are specifically testing for a false value, but in other cases, you can do: 
if ( ($params->{root} || '') eq 'foo' )

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The other thing to consider is why you have so many possible undefs; could you be initializing things, providing default values, using NOT NULL columns, etc. to avoid the possibility of undefs in some cases?

In reply to Re: complaint: always testing defined() by ysth
in thread complaint: always testing defined() by RaptorRex

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