Created
December 5, 2018 21:05
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Definition bag := nat. | |
Existing Class bag. | |
Instance : bag := 5. | |
Instance : bag := 6. | |
Instance : bag := 7. | |
Instance : bag := 8. | |
Instance : bag := 9. | |
Ltac tryeach cls t := | |
let picked := fresh "picked" in | |
unshelve (idtac; let v := open_constr:(let picked : cls := _ in _) in exact v); | |
[ typeclasses eauto | | |
let picked := eval unfold picked in picked in | |
let picked := eval unfold picked in picked in | |
t picked | |
]; | |
clear picked. | |
Goal exists x, x=7. | |
eexists. | |
Set Typeclasses Debug. | |
tryeach bag ltac:(fun x => exact (eq_refl x)). | |
Qed. |
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