[Puppet Users] :merge_behavior: deeper and hiera_hash

Per the docs, the :merge_behavior setting affects how hashes are merged in
a "hash merge lookup". Not every hiera lookup is a hash merge lookup, and
whether a query is of that kind does not depend on the type of the data
retrieved. A standard hiera lookup, such as is performed by the ordinary
hiera() function, simply returns the highest-priority datum it finds in the
data hierarchy. This is what is used for automated class parameter
binding. A hash merge lookup, on the other hand, is what you get from the
hiera_hash() function.



John

Makes sense.

I think that the confusion stems from using on hiera_include's array merge
lookup, seeing your class arrays being merged nicely and assuming such
behaviour extends to class parameter binding. I understand the reasons
maintaining priority lookup for class parameters though.