Action plan

1. Stage - model parser

1. Reimplement current parser to use visitor pattern. I propose to move all static methods from_etree to V2Visitor. With this name scheme _from_etree. e. g. schema_from_etree. Overload get attribute to raise PyModelException(unsupported tag in this version?) when unimplemented form_etree is called

• Where to storage primitive types?

2. Implement V4 parser. Shared parser implementation with V2 can be moved to mixins. This includes adding support for:

• Function, Action and ActionImports
• Alias attribute on all tags
• Include -> which can contain new metadata
• Add support for new types and remove deprecated ones -> see Changes in types
• Notable changes will be done to Associations
• Do not forget about EntityType -> BaseType attribute
• Add navigation property to complex type -> To existing class or create a new one for v4?
• let's not do annotations for now