[racket-dev] parse errors in types, poly-dots cause me headaches

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Tue Nov 18 11:54:13 EST 2014

On Nov 18, 2014, at 11:34 AM, Sam Tobin-Hochstadt <samth at cs.indiana.edu> wrote:

> On Tue, Nov 18, 2014 at 10:45 AM, Matthias Felleisen
> <matthias at ccs.neu.edu> wrote:
>> It's quite possible that this is Eli's bug again, but boy this causes headaches:
>>> Type Checker: parse error in type;
>>> type variable must be used with ...
>>>  variable: Y in: Y
>> And it points precisely to where Y is followed by ...
> The problem here is that you're using ->* without using the syntax of
> ->*.  Fortunately, this program doesn't need ->* at all.
> Unfortunately, I don't know how to make this function type check yet,
> but I'll keep playing with it.

Are you blaming the victim here? Please run what I send out and experience how the type checker barfs on you. This is a bug report. 

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