33 lines
1.4 KiB
Racket
33 lines
1.4 KiB
Racket
#lang s-exp "typecheck.rkt"
|
|
(extends "sysf.rkt" #:except #%datum ∀ Λ inst)
|
|
(reuse String #%datum #:from "stlc+reco+var.rkt")
|
|
(reuse current-kind? ∀★ ∀★? ★ ★? kind? ∀ Λ inst define-type-alias #:from "fomega.rkt")
|
|
|
|
; same as fomega2.rkt --- λ and #%app works as both regular and type versions,
|
|
; → is both type and kind --- but reuses parts of fomega.rkt,
|
|
; ie removes the duplication in fomega2.rkt
|
|
|
|
;; System F_omega
|
|
;; Type relation:
|
|
;; - redefine current-kind? and current-type so #%app and λ
|
|
;; work for both terms and types
|
|
;; Types:
|
|
;; - types from fomega.rkt
|
|
;; - String from stlc+reco+var
|
|
;; Terms:
|
|
;; - extend ∀ Λ inst from fomega.rkt
|
|
;; - #%datum from stlc+reco+var
|
|
|
|
;; types and kinds are now mixed, due to #%app and λ
|
|
(begin-for-syntax
|
|
(current-kind? (λ (k) (or (#%type? k) (kind? k) (#%type? (typeof k)))))
|
|
;; Try to keep "type?" backward compatible with its uses so far,
|
|
;; eg in the definition of λ or previous type constuctors.
|
|
;; (However, this is not completely possible, eg define-type-alias)
|
|
;; So now "type?" no longer validates types, rather it's a subset.
|
|
;; But we no longer need type? to validate types, instead we can use (kind? (typeof t))
|
|
(current-type? (λ (t) (or (type? t)
|
|
(let ([k (typeof t)])
|
|
(or (★? k) (∀★? k)))
|
|
((current-kind?) t)))))
|