[racket] TR Numeric Tower

20 minutes ago, Matthias Felleisen wrote:
> That's just semantics, you dang logician 

(And it shows why "types = documentation" is more often false than
people who are head-deep in types tend to think...)


> On Feb 13, 2013, at 10:09 PM, Carl Eastlund wrote:
> 
>     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)))
>         >
>         >
>         > ____________________
>         >  Racket Users list:
>         >  http://lists.racket-lang.org/users
>        
>         ____________________
>           Racket Users list:
>           http://lists.racket-lang.org/users
> 
> ____________________
>   Racket Users list:
>   http://lists.racket-lang.org/users

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!