e53f944c83
This PR improves the error message displayed when writing an invalid projection on a free variable of function type.
108 lines
2.1 KiB
Text
108 lines
2.1 KiB
Text
/-!
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# Invalid field notation on expressions of function type
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Ensure we produce correct field notation error messages for expressions of function type and not the
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fallback "type is not of the form `C ...`" message.
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-/
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set_option pp.mvars false
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def foo : α → α := id
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/-- error: Unknown constant `foo.bar` -/
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#guard_msgs in
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example := foo.bar
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/--
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error: Invalid field `foo`: The environment does not contain `Function.foo`
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fun x => x
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has type
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?_ → ?_
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-/
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#guard_msgs in
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example (f : α → α) := (fun x => x).foo
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/--
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error: Invalid field `foo`: The environment does not contain `Function.foo`
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f
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has type
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α → α
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-/
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#guard_msgs in
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example (f : α → α) := f.foo
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/--
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error: Invalid field notation: Type is not of the form `C ...` where C is a constant
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f x
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has type
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α
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-/
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#guard_msgs in
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example (f : α → α) (x : α) := (f x).foo
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/--
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error: Invalid field `foo`: The environment does not contain `Function.foo`
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f x
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has type
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α → α
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-/
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#guard_msgs in
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example (f : α → α → α) (x : α) := (f x).foo
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/--
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error: Invalid field notation: Type is not of the form `C ...` where C is a constant
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foo x
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has type
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α
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-/
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#guard_msgs in
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example (x : α) := (foo x).foo
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def foo.bar := 32
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/--
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error: Invalid field `bar`: The environment does not contain `Function.bar`
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foo
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has type
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α → α
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-/
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#guard_msgs in
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example (foo : α → α) := foo.bar
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/--
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error: Invalid field `foo`: The environment does not contain `Function.foo`
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let x := id;
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x
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has type
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?_ → ?_
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-/
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#guard_msgs in
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example := (let x := id; x).foo
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/--
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error: Invalid field `foo`: The environment does not contain `Function.foo`
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?_
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has type
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α → α
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-/
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#guard_msgs in
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example {α} := (by intro h; exact h : α → α).foo
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/-! Make sure we're not overzealously detecting fvars or implicitly-parameterized values in function position -/
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/--
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error: Invalid field `foo`: The environment does not contain `Nat.foo`
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n
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has type
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Nat
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-/
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#guard_msgs in
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example (n : Nat) := n.foo
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/--
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error: Invalid field `foo`: The environment does not contain `List.foo`
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[]
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has type
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List Nat
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-/
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#guard_msgs in
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example (n : Nat) := (@List.nil Nat).foo
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