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W types in Formality
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| W(A : Type, B : A -> Type) : Type | |
| w<P : W(A,B) -> Type> -> | |
| (sup : (x: A, f: B(x) -> W(A,B)) -> P(W.sup<A,B>(x,f))) -> | |
| P(w) | |
| W.sup<A: Type, B: A -> Type>(x: A, f: B(x) -> W(A,B)) : W(A,B) | |
| <P> (sup) sup(x,f) | |
| T Two | |
| | t0; | |
| | t1; | |
| Nwf(t: Two): Type | |
| case t: | |
| | Empty; | |
| | Unit; | |
| Nw : Type | |
| W(Two,Nwf) | |
| nw0 : Nw | |
| W.sup<Two,Nwf>(t0, (v) Empty.absurd<W(Two,Nwf)>(v)) | |
| nw1 : Nw | |
| W.sup<Two,Nwf>(t1, (v) nw0) |
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