Remove levels from the universe

This commit is contained in:
Yiyun Liu 2025-05-13 19:13:44 -04:00
parent f5fe22c419
commit c6528de647
2 changed files with 11 additions and 11 deletions

View file

@ -83,7 +83,7 @@
`(succ ,a))
(check-equal? (normalize `(app ,tm-id ,tm-id)) tm-id)
(check βη-eq? `(app ,tm-id (U 0)) '(U 0))
(check βη-eq? `(app ,tm-id U) 'U)
(check-equal? (normalize `(app (app (app ,tm-pair ,tm-id) ,tm-fst) ,tm-snd)) tm-fst)
(check-equal? (normalize `(app (app (app ,tm-pair ,tm-id) ,tm-fst) ,tm-fst)) tm-id)
(check-equal? (normalize (tm-app tm-snd (tm-app tm-pair tm-id tm-fst) tm-fst)) tm-fst)
@ -97,10 +97,10 @@
(tm-pnat 12000))
(check βη-eq? (tm-padd (tm-pnat 10000) (tm-pnat 2000)) (tm-pnat 12000))
(check βη-eq? (tm-abs (tm-app (tm-var 1) (tm-var 0))) (tm-app tm-id (tm-var 0)))
(check βη-eq? `(Π (U 0) (Π (var 0) ,(tm-app tm-id '(var 1)))) '(Π (U 0) (Π (var 0) (var 1))))
(check βη-eq? `(Π U (Π (var 0) ,(tm-app tm-id '(var 1)))) '(Π U (Π (var 0) (var 1))))
(check-false (βη-eq? '(succ zero) '(var 0)))
(check βη-eq? (tm-app (tm-var 0) (tm-var 1)) (tm-app (tm-var 0) (tm-var 1)))
(check βη-eq? (tm-ind (tm-var 0) (tm-var 1) (tm-var 2)) (tm-ind (tm-var 0) (tm-var 1) (tm-var 2)))
(check-false (βη-eq? (tm-abs (tm-app (tm-var 1) (tm-var 0))) (tm-app tm-id (tm-var 1))))
(check-false (βη-eq? (tm-app (tm-var 0) (tm-var 0)) (tm-ind (tm-var 0) 'zero 'zero)))
(check-false (βη-eq? '(U 0) '(var 0)))
(check-false (βη-eq? 'U '(var 0)))

16
nbe.rkt
View file

@ -10,14 +10,14 @@
(List 'app Term Term)
(List 'ind Term Term Term)
(List 'Π Term Term)
(List 'U V)))
'U))
(define-type D ( 'zero
(List 'Π (Promise D) (-> (Promise D) D))
(List 'succ (Promise D))
(List 'fun (-> (Promise D) D))
(List 'neu D-ne)
(List 'U V)))
'U))
(define-type D-ne ( (List 'app D-ne D)
(List 'idx V)
@ -56,7 +56,7 @@
(: interp (-> Term denv D))
(define (interp a ρ)
(match a
[`(U ,_) a]
['U a]
[`(Π ,A ,B) `(Π ,(delay (interp A ρ)) ,(interp-fun B ρ))]
[`(var ,i) (force (ρ i))]
['zero 'zero]
@ -83,7 +83,7 @@
(and (compare n (force A0) (force A1))
(compare (add1 n) (open-dom n B0) (open-dom n B1)))]
['(nat nat) #t]
[`((U ,i) (U ,j)) (eqv? i j)]
['(U U) #t]
['(zero zero) #t]
[`((succ ,a) (succ ,b)) (compare n (force a) (force b))]
[`((fun ,f) (neu ,u)) (compare (add1 n) (open-dom n f) `(neu (app ,u (neu (idx ,n)))))]
@ -107,7 +107,7 @@
[`(Π ,A ,B) `(Π ,(reify n (force A)) ,(reify (+ n 1) (B (delay `(neu (idx ,n))))))]
['zero 'zero]
[`(succ ,a) `(succ ,(reify n (force a)))]
[`(U ,_) a]
['U a]
[`(fun ,f) (list 'λ (reify (+ n 1) (f (delay `(neu (idx ,n))))))]
[`(neu ,a) (reify-neu n a)]))
@ -137,7 +137,7 @@
(define (scope a)
(match a
[`(Π ,A ,B) (max (scope A) (- (scope B) 2))]
[`(U ,_) 0]
['U 0]
['zero 0]
[`(succ ,a) (scope a)]
(`(ind ,a ,b ,c) (max (scope a) (scope b) (- (scope c) 2)))
@ -162,7 +162,7 @@
(: subst (-> (-> V Term) Term Term))
(define (subst ρ a)
(match a
[`(U ,_) a]
['U a]
[`(Π ,A ,B) `(Π ,(subst ρ A) ,(subst (up 1 ρ) B))]
[`(var ,i) (ρ i)]
[`(app ,a ,b) `(app ,(subst ρ a) ,(subst ρ b))]
@ -182,7 +182,7 @@
(: η-eq? (-> Term Term Boolean))
(define (η-eq? a b)
(match (list a b)
[`((U ,i) (U ,j)) (eqv? i j) ]
['(U U) #t ]
[`((Π ,A0 ,B0) (Π ,A1 ,B1))
(and (η-eq? A0 A1) (η-eq? B0 B1))]
['(zero zero) true]