suzanne.soy/racket
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add back some special cases.

Browse Source
This commit is contained in:
Sam Tobin-Hochstadt 2012-08-07 15:35:27 -04:00
parent 21598297a7
commit 7eaae20f41
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
collects/typed-racket/types/union.rkt
View File

@ -34,9 +34,17 @@
[(Union: es) es] [(Union: es) es]
[_ (list t)])) [_ (list t)]))
(define empty-union (make-Union null))
;; Union constructor ;; Union constructor
;; Normalizes representation by sorting types. ;; Normalizes representation by sorting types.
;; Type * -> Type ;; Type * -> Type
;; The input types can overlap and be union types ;; The input types can overlap and be union types
(define (Un . args) (define Un
(make-union* (foldr merge '() (remove-dups (sort (append-map flat args) type<?))))) (case-lambda
[() empty-union]
[(t) t]
[args
(define ts (foldr merge '()
(remove-dups (sort (append-map flat args) type<?))))
(make-union* ts)]))