70b181d88f
Before this commit, the unifier would try to solve the unification consraint
?m =?= fun x_1 ... x_n, ?m x_1 ... x_n
by assigning
?m := fun x_1 ... x_n, ?m x_1 ... x_n
which fails the occurs check.
This commit skips the assignment by using eta-reduction.
26 lines
619 B
Text
26 lines
619 B
Text
open tactic
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example : true :=
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by do
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let n : expr := `(nat),
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let t : expr := `(nat → nat),
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m ← mk_meta_var t,
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let em : expr := (expr.lam `x binder_info.default n (expr.app m (expr.var 0))),
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/- The unification constraint
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?m =?= (fun x, ?m x)
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should work.
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-/
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unify m em,
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constructor
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example : true :=
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by do
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let n : expr := `(nat),
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let t : expr := `(nat → nat),
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m ← mk_meta_var t,
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let em : expr := (expr.lam `x binder_info.default n (expr.app m (expr.var 0))),
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/- The unification constraint
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?m =?= (fun x, ?m x)
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should work.
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-/
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unify em m,
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constructor
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