[racket] Typed racket and keywords

From: Norman Gray (norman at astro.gla.ac.uk)
Date: Thu Feb 21 18:03:34 EST 2013

Sam, hello.

On 2013 Feb 21, at 22:56, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:

> Thinking about it further, it's possible to enforce this invariant
> statically.  Unfortunately TR isn't smart enough to let you express
> this in the nicest way possible, but if you look at the above gist
> now, it shows an example of the type system rejecting the errors that
> you're catching dynamically.

Many thanks for this -- I shall meditate on this tomorrow.

I suspect that I'm confusing myself by trying to solve two problems simultaneously, namely enforcing the invariant and trying to work out how to type a closure.  I've gone round in so many circles today that I'm dizzy and that probably shows in the examples.

Best wishes,


Norman Gray  :  http://nxg.me.uk
SUPA School of Physics and Astronomy, University of Glasgow, UK

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