[Bf-python] BMesh API

[Treyer Lukas]

Well. Then I would probably prefer to write a wrapper for the wrapper… as proposed here
http://stackoverflow.com/questions/399022/why-cant-i-subclass-datetime-date

With normal bpy.types.MeshPolygon.customdata = bpy.props.IntProperty() I can add properties. 
With Bmesh this is not possible. Why?

>>> bmesh.types.BMFace.custom = bpy.props.StringProperty(name="my", default="String")
TypeError: can't set attributes of built-in/extension type 'BMFace'

What are the existing primitive data you mention? Are we talking about Python or C API of BMesh?
Assuming you're talking about C functions in your step by step instructions: I don't want to add anything in C. I want my python code to run with an official Blender release.