Well-founded recursion with copatterns and sized types

@article{Abel2016WellfoundedRW,
  title={Well-founded recursion with copatterns and sized types},
  author={Andreas Abel and Brigitte Pientka},
  journal={Journal of Functional Programming},
  year={2016},
  volume={26}
}
Abstract In this paper, we study strong normalization of a core language based on System ${\mathsf{F}_\omega}$ which supports programming with finite and infinite structures. Finite data such as finite lists and trees is defined via constructors and manipulated via pattern matching, while infinite data such as streams and infinite trees is defined by observations and synthesized via copattern matching. Taking a type-based approach to strong normalization, we track size information about finite… 
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