Coercive Subtyping

@article{Luo1999CoerciveS,
  title={Coercive Subtyping},
  author={Zhaohui Luo},
  journal={J. Log. Comput.},
  year={1999},
  volume={9},
  pages={105-130}
}
  • Zhaohui Luo
  • Published 1999
  • Computer Science
  • J. Log. Comput.
We propose and study coercive subtyping, a formal extension with subtyping of dependent type theories such as Martin-LL of's type theory 38] and the type theory UTT 30]. In this approach, subtyping with speciied implicit coercions is treated as a feature at the level of the logical framework; in particular, the meaning of an object being in a supertype is given by coercive deenition rules for the deenitional equality. This provides a conceptually simple and uniform framework to understand… 
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In this approach, subtyping with specified implicit coercions is treated as a feature at the level of the logical framework; in particular, subsumption and coercion are combined in such a way that the meaning of an object being in a supertype is given by coercive definition rules for the definitional equality.
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