[racket-dev] Should I expect this program to typecheck?

From: Neil Toronto (neil.toronto at gmail.com)
Date: Mon Aug 6 16:12:53 EDT 2012

#lang typed/racket

(: vector-first (All (A B) ((U (Vectorof A) (Vectorof B)) -> (U A B))))
(define (vector-first vs)
   (vector-ref vs 0))

I can't think of a reason this shouldn't work, but I may not be taxing 
my imagination enough to come up with one.

Neil ⊥

Posted on the dev mailing list.