How do I tell what type of value is in a Perl variable?

Question

How do I tell what type of value is in a Perl variable?

$x might be a scalar, a ref to an array or a ref to a hash (or maybe other things).

Answer 1

ref():

Perl provides the ref() function so that you can check the reference type before dereferencing a reference...

By using the ref() function you can protect program code that dereferences variables from producing errors when the wrong type of reference is used...