diff options
Diffstat (limited to 'stlc-let.rkt')
| -rw-r--r-- | stlc-let.rkt | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/stlc-let.rkt b/stlc-let.rkt index 3d6afc6..04dbd84 100644 --- a/stlc-let.rkt +++ b/stlc-let.rkt @@ -4,18 +4,18 @@ ;; The Simply-Typed Lambda Calculus, with let sugar and some base types ;; (interpret Expr Table[Sym, Expr]): Value -(define (interpret expr [ctx #hash()]) - (interpret- (strip (desugar expr)) ctx)) -(define (interpret- expr ctx) +(define (interpret expr [Γ #hash()]) + (interpret- (strip (desugar expr)) Γ)) +(define (interpret- expr Γ) (match expr ['sole 'sole] [n #:when (natural? n) n] - [x #:when (dict-has-key? ctx x) (dict-ref ctx x)] - [`(λ ,x ,e) `(λ ,x ,e ,ctx)] + [x #:when (dict-has-key? Γ x) (dict-ref Γ x)] + [`(λ ,x ,e) `(λ ,x ,e ,Γ)] [`(,e1 ,e2) - (match (interpret- e1 ctx) - [`(λ ,x ,e1 ,env) (interpret- e1 (dict-set env x (interpret- e2 ctx)))] - [e1 `(,e1 ,(interpret- e2 ctx))])] + (match (interpret- e1 Γ) + [`(λ ,x ,e1 ,env) (interpret- e1 (dict-set env x (interpret- e2 Γ)))] + [e1 `(,e1 ,(interpret- e2 Γ))])] [e e])) ;; (check Expr Type Table[Sym, Type]): Bool |