Towards projection: mapping reflection onto the userland

Allowing end-users to extend and adapt applications can speedup software evolution and serve as a pedagogical tool for programming. Alas even open-ended architectures (like the Emacs architecture) presuppose a significant familiarity with programming languages and tools for end-users. General visual programming (as in the case of blocks) offers a more gentle alternative but still introduces additional tools and cognitive abstractions for prospective developers. We propose a possible third alternative: the direct mapping of reflective and meta-programming facilities onto base-level notions and interfaces through an additional self representation model, the projection layer. Our main hypothesis is that for certain types of applications used by non programmers (like for e.g., simulation software) this projection to the base-level has the potential to open a more gradual learning path for programming extensions, by using the same UI and abstractions that the end-user is already familiar with. This position paper analyses our approach and describes our on-going efforts to support or refute our hypothesis through a case-study on software for crisis assessment.