A Boolean context doesn't have to take only a comparison (==, !=, <, >=, etc.). Any value (including the value returned by LastError()) can be tested for truth. perldoc perldata says:
A scalar value is interpreted as TRUE in the Boolean sense if it is not the null string or the number 0 (or its string equivalent, "0"). The Boolean context is just a special kind of scalar context where no conversion to a string or a number is ever performed.
See What is true and false in Perl? for a longer discussion.

In reply to Re: Boolean?? by ysth
in thread Boolean?? by mbayer

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