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

From: J. Ian Johnson (ianj at ccs.neu.edu)
Date: Mon Aug 6 16:25:35 EDT 2012

How do you determine the difference between the two vector types is the question...
----- Original Message -----
From: "Neil Toronto" <neil.toronto at gmail.com>
To: "<dev at racket-lang.org>" <dev at racket-lang.org>
Sent: Monday, August 6, 2012 4:12:53 PM GMT -05:00 US/Canada Eastern
Subject: [racket-dev] Should I expect this program to typecheck?

#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 ⊥
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