20 lines
732 B
Markdown
20 lines
732 B
Markdown
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Things I would do differently with hindsight:
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* Make pointed dependent maps primitive:
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```lean
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structure ppi (A : Type*) (P : A → Type) (p : P pt) :=
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(to_fun : Π a : A, P a)
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(resp_pt : to_fun (Point A) = p)
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```
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(maybe the last argument should be `[p : pointed (P pt)]`). Define pointed (non-dependent) maps as a special case.
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Note: assuming `P : A → Type*` is not general enough.
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* Use squares, also for maps, pointed maps, ... heavily
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* Type classes for equivalences don't really work
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* Coercions should all be defined *immediately* after defining a structure, *before* declaring any
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instances. This is because the coercion graph is updated after each declared coercion.
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* [maybe] make bundled structures primitive
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