Questions tagged [subtyping]
Use this tag for polymorphism that restrict the range of types that can be used in a particular case.
3
questions
9
votes
2
answers
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What's the benefit of having pi and sigma types with an invariant parameter?
Ulf Norell wrote this in his PhD thesis (figure 1.6):
This contradicts my stereotype on pi & sigma types, where pi parameter should be contravariant and sigma parameter is covariant. Why is Agda ...
- 5,802
5
votes
1
answer
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What subtyping rules does Agda support?
Andrea Vezzosi said Cubical Agda made cubical subtyping coercion-based (inS and outS) because it's a bad idea to introduce more ...
- 5,802
14
votes
2
answers
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Formal description of algorithmic subtyping/cumulativity
Are there any references (papers, documentation, etc.) for how proof assistants with subtyping due to cumulativity actually implement algorithmic subtyping? Coq, for instance, has subtyping, but the ...
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