And the additional benefit to be able to test for the type of a scalar which happens to be passed to me, by checking for ref $fh eq 'IO::File'.
Please don't do that. Your code is fragile. It will break when I pass an object that subclasses IO::File but acts in every way like an IO::File.

Instead, write your code so that the class doesn't matter. Use the polymorphism as it was intended. If you are unsure if $object_x can handle a particular method call, then use UNIVERSAL::can against it, or put it in an eval block to trap the potential error.

The use of ref in ordinary code should be limited to determining whether something is a reference or not (such as whether the first parameter for a method call is a class or instance). Any explicit comparison will break subclassing. Too much "navel contemplation" is a bad thing in robust code.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to Say no to ref $thing eq "Expected::Type" by merlyn
in thread Putting file contents into a scalar by ByteOrNybble

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