603dafbaf7
We simulate it in the following way:
1- An opaque 'let'-expressions (let x : t := v in b) is encoded as
((fun (x : t), b) v)
We also use a macro (let-macro) to mark this pattern.
Thus, the pretty-printer knows how to display it correctly.
2- Transparent 'let'-expressions are eagerly expanded by the parser.
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
7 lines
1.9 KiB
Text
7 lines
1.9 KiB
Text
let and_intro : Pi (p : Bool) (q : Bool) (H1 : p) (H2 : q), ((fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q) := fun (p : Bool) (q : Bool) (H1 : p) (H2 : q) (c : Bool) (H : p -> q -> c), (H H1 H2) in (let and_elim_left : Pi (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), p := fun (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), (H p (fun (H1 : p) (H2 : q), H1)) in (let and_elim_right : Pi (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), q := fun (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), (H q (fun (H1 : p) (H2 : q), H2)) in and_intro)) : Pi (p : Bool) (q : Bool) (H1 : p) (H2 : q), ((fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q)
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let1.lean:17:20: error: type mismatch at application
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(fun (and_intro : Pi (p : Bool) (q : Bool) (H1 : p) (H2 : q), ((fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) q p)), (let and_elim_left : Pi (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), p := fun (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), (H p (fun (H1 : p) (H2 : q), H1)) in (let and_elim_right : Pi (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), q := fun (p : Bool) (q : Bool) (H : (fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) p q), (H q (fun (H1 : p) (H2 : q), H2)) in and_intro))) (fun (p : Bool) (q : Bool) (H1 : p) (H2 : q) (c : Bool) (H : p -> q -> c), (H H1 H2))
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expected type:
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Pi (p : Bool) (q : Bool) (H1 : p) (H2 : q), ((fun (p : Bool) (q : Bool), (Pi (c : Bool) (a : p -> q -> c), c)) q p)
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given type:
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Pi (p : Bool) (q : Bool) (H1 : p) (H2 : q) (c : Bool) (H : p -> q -> c), c
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