Change default jsonapi_namespace_separator to --

[westoque]

Currently, the default has been to dasherize the namespaced model. For example Admin::User to admin-user. This is bad because the default and standard behavior for camel casing and dasherizing models was from a structure that looks like MyCamelCase to my-camel-case.

So if you read the namespaced model admin-user, from the looks of it, you are expecting AdminUser but in reality, is just a namespace. It would be better written admin--user by default.

[bf4]

@westoque yes, we actually recommend this in our docs https://github.com/rails-api/active_model_serializers/blob/v0.10.4/docs/general/configuration_options.md#jsonapi_namespace_separator

Changing it, however, is a breaking change, so will have to wait for a major version :(