feat: partial inhabitation uses local Inhabited instances created from parameters
#5821
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… from parameters Rather than having a special pass where `mkInhabitantFor` uses the `assumption` tactic, it creates `Inhabited` instances for each parameter and just searches for an `Inhabited` instance for the return type. This makes examples like the following work: ```lean partial def f (x : X) : Bool × X := ... ```
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Since `partial` inhabitation is stronger in leanprover#5821, this private instance is no longer needed.
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Since `partial` inhabitation is stronger in #5821, this private instance is no longer needed.
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… from parameters (leanprover#5821) Rather than having a special pass where `mkInhabitantFor` uses the `assumption` tactic, it creates `Inhabited` instances for each parameter and just searches for an `Inhabited`/`Nonempty` instance for the return type. This makes examples like the following work: ```lean partial def f (x : X) : Bool × X := ... ``` Removes the strategy where it looks for `Inhabited`/`Nonempty` instances for every suffix of the signature. This is a follow-up to leanprover#5780. Motivated [by Zulip](https://leanprover.zulipchat.com/#narrow/channel/113489-new-members/topic/Why.20return.20type.20of.20partial.20function.20MUST.20.60inhabited.60.3F/near/477905312).
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Since `partial` inhabitation is stronger in leanprover#5821, this private instance is no longer needed.
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Rather than having a special pass where
mkInhabitantForuses theassumptiontactic, it createsInhabitedinstances for each parameter and just searches for anInhabited/Nonemptyinstance for the return type.This makes examples like the following work:
Removes the strategy where it looks for
Inhabited/Nonemptyinstances for every suffix of the signature.This is a follow-up to #5780. Motivated by Zulip.