feat: make Function generalized field notation more usable#13244
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feat: make Function generalized field notation more usable#13244
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This PR changes two aspects of generalized field notation for functions to make it more usable. First, the resolution rules for functions and the `Function` pseudo-structure are the same as for other structures, so now `f.foo` resolves `Function.foo` using the currently open namespaces, and it can be used for defining recursive functions (e.g. `Function.iterate`). Second, generalized field notation for functions has an additional rule that it only matches the first *explicit* function argument, which makes it possible to use dot notation with implicit arguments that are type families. Addresses the `Function.swap` example from issue #1629, and an issue from [Zulip](https://leanprover.zulipchat.com/#narrow/channel/113489-new-members/topic/generalized.20field.20notation.20vs.20namespaces/near/582689850).
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This PR changes two aspects of generalized field notation for functions to make it more usable. First, the resolution rules for functions and the
Functionpseudo-structure are the same as for other structures, so nowf.fooresolvesFunction.foousing the currently open namespaces, and it can be used for defining recursive functions (e.g.Function.iterate). Second, generalized field notation for functions has an additional rule that it only matches the first explicit function argument, which makes it possible to use dot notation with implicit arguments that are type families.Addresses the
Function.swapexample from issue #1629, and an issue from Zulip.