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

The safety in this case doesn't generalize to contracts like the one
Neil is suggesting when you go from an untyped value to a typed one,
tho, right?

Robby

On Tue, Jun 26, 2012 at 8:32 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:
> Certainly the dependent contract approach will work, but the 'Real -> Real'
> contract is also safe, so I'll see about generating that.
>
> Sam
>
> On Jun 26, 2012 8:37 PM, "Robby Findler" <robby at eecs.northwestern.edu>
> 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
>>
>> _________________________
>>  Racket Developers list:
>>  http://lists.racket-lang.org/dev