Discussion on how to handle reopening exposures.

Example.

class Person < Grape::Entity
  expose :user do
    expose(:in_first) { |_| 'value' }
  end
end

class Student < Person
  expose :user do
    expose(:user_id) { |_| 'value' }
    expose(:user_display_id, as: :display_id) { |_| 'value' }
  end
end

• Current behaviour is that both exposures are merged.
• @dblock expressed his concern that this does not follow the same logic as redefining a method: The old method gets overwritten; so if you want to call it, you would use super.

related: https://github.com/intridea/grape-entity/pull/63

No implementation file or test is named. Start by reading the exposure-inheritance example and related pull request #63, then establish whether reopening should merge exposures or replace them; the issue is done only once the project agrees on the behavior and its expected coverage.