Confused about Value and Item

Hi all,

I'm writing a Perl book and I'm on an introductory Moose chapter. I'm including the following list of types from Moose::Util::TypeConstraints:

  Any
  Item
      Bool
      Maybe[`a]
      Undef
      Defined
          Value
              Str
                  Num
                      Int
                  ClassName
                  RoleName
          Ref
              ScalarRef[`a]
              ArrayRef[`a]
              HashRef[`a]
              CodeRef
              RegexpRef
              GlobRef
              FileHandle
              Object

In trying to explain this, I got stuck on "Item" and "Value". I have the following note about them:

A word about the types in Moose::Util::TypeConstraints. "Any" means "anything"
>(duh). An "Item" is the same as "Any" and in your author's consultation with
>Moose experts, there was confusion expressed as to why these were different
>
>
>A "Value" is "anything which is defined and not a reference". But since
>everything which is a "Value" is also a "Str" (String) type, it's also unclear why
>"Value" was included, except for possibly defining future types which may apply.

I really would love to have a better understanding of this so that I can omit this note :)
 
Cheers,
Ovid
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