[racket-dev] math collection [was: Hyperbolic functions]

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Tue Jun 26 21:27:51 EDT 2012

Well, you wouldn't. Are the implementations of the contracts proven to
be equivalent currently? Or do you just have a theorem that matches up
the ones in some model somewhere?

Robby

On Tue, Jun 26, 2012 at 8:05 PM, Matthias Felleisen
<matthias at ccs.neu.edu> wrote:
>
> How would you check soundness between a type and its contract?
>
> Types, like theorem provers, are addictive. The more expressivity
> they provide, the more programmers want to play with them.
>
> Use Real -> Real and you'll be fine. -- Matthias
>
>
>
> On Jun 26, 2012, at 8:37 PM, Robby Findler wrote:
>
>> In this case, the contract could turn into a dependent one with the
>> same semantics. Does it make sense for TR to allow a user to declare
>> the equivalent contract?
>>
>> Robby
>>
>> On Tue, Jun 26, 2012 at 7:17 PM, Neil Toronto <neil.toronto at gmail.com> wrote:
>>> Ten minutes in, I've hit a snag. I'd like the stuff in math/functions to
>>> have precise types. For example, log1p could have the type
>>>
>>>  (case-> (Zero -> Zero)
>>>          (Float -> Float)
>>>          (Real -> Real))
>>>
>>> It was easy to get the implementation to typecheck, but when I tried to plot
>>> it in untyped Racket, I got this:
>>>
>>>  Type Checker: The type of log1p cannot be converted to a contract in: log1p
>>>
>>> I really don't want to have two versions of the library. Could TR use the
>>> most general type (Real -> Real) as the contract? Or would that be unsound?
>>>
>>> Neil ⊥
>>> _________________________
>>>  Racket Developers list:
>>>  http://lists.racket-lang.org/dev
>>
>> _________________________
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>>  http://lists.racket-lang.org/dev
>


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