[racket] TR Numeric Tower

That might not be what he wants either, if he wants anything representable
as a flonum to be a flonum.  For instance, (S->F "5") is #false by your
implementation.  It's hard to tell exactly what S->F is supposed to do
without more of a specification.

Carl Eastlund


On Wed, Feb 13, 2013 at 10:04 PM, Matthias Felleisen
<matthias at ccs.neu.edu>wrote:

>
> #lang typed/racket
>
> (: S->F : String -> (Option Float))
> (define (S->F s)
>   (define n (string->number s))
>   (and (flonum? n) n))
>
> I assume you mean to convert strings into floats, if possible.
>
> But you may like the funny answers better -- Matthias
>
>
>
> On Feb 13, 2013, at 9:49 PM, Ray Racine wrote:
>
> > What is the most efficient way to write the following method in TR?
> >
> > (: S->F (String -> (Option Float)))
> >
> >
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