caf815b009
This PR improves the message and range of infer binder type failures. --------- Co-authored-by: Joseph Rotella <7482866+jrr6@users.noreply.github.com>
23 lines
465 B
Text
23 lines
465 B
Text
/-!
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# Eta arguments had wrong context in "don't know how to synthesize implicit" errors
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https://github.com/leanprover/lean4/issues/5475
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-/
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set_option pp.mvars false
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/-!
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Formerly, argument `x` appeared as `_fvar.123`
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-/
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def f {α β : Type} (x: α) (y: β) : α := x
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/--
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error: don't know how to synthesize implicit argument 'α'
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@f ?_ Nat x Nat.zero
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context:
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⊢ Type
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---
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error: Failed to infer type of example
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-/
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#guard_msgs in
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example :=
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f (y := Nat.zero)
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