diff options
Diffstat (limited to 'stlc-fix.rkt')
| -rw-r--r-- | stlc-fix.rkt | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/stlc-fix.rkt b/stlc-fix.rkt index f5ad384..bcb28cb 100644 --- a/stlc-fix.rkt +++ b/stlc-fix.rkt @@ -4,27 +4,27 @@ ;; The Simply-Typed Lambda Calculus, with general recursion ;; (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)] + [x #:when (dict-has-key? Γ x) (dict-ref Γ x)] [`(fix ,e) - (match (interpret- e ctx) + (match (interpret- e Γ) [`(λ ,x ,e ,env) - ; FIXME: unsure what should be ctx and what should be env - (interpret- e (dict-set ctx x `(fix (λ ,x ,e ,ctx))))] + ; FIXME: unsure what should be Γ and what should be env + (interpret- e (dict-set Γ x `(fix (λ ,x ,e ,Γ))))] [e (err (format "applying fix to unknown expression ~a" e))])] - [`(λ ,id ,body) `(λ ,id ,body ,ctx)] + [`(λ ,id ,body) `(λ ,id ,body ,Γ)] [`(λ ,id ,body ,env) `(λ ,id ,body ,env)] [`(,body ,arg) - (match (interpret- body ctx) + (match (interpret- body Γ) [`(λ ,id ,body ,env) - (interpret- body (dict-set env id (interpret- arg ctx)))] + (interpret- body (dict-set env id (interpret- arg Γ)))] [e (err (format "applying arg ~a to unknown expression ~a" arg e))])] [e (err (format "interpreting an unknown expression ~a" e))])) |