Re: dylan scientific/multimedia

[Simon Spero <ses@sunsite.unc.edu>]

[meta-note: I only just got added to the lists, so I'm still not 100% 
 up to speed- are the archives  available for WAIS/FTP anywhere?]

   zilla@ccrl.nj.nec.com (John Lewis) writes:
>
>Are there currently any Lisp implementations which do floating point
>very efficiently?  I don't know of any, so I'm not expecting this
>from Dylan either, but it would be nice.

If there's sufficient type information available at compile-time, lisp
is as fast as fortran. It's only when the types are unknown and you have to
dispatch at run-time that things really start to slow down. 

>- That Dylan provide for homogeneous arrays of short floats and ints.
>  If not, vectorized coding can still be done by allocating foreign storage
>  on the heap and manipulating this with the C-coded vector ops.
>  Someone borrowed my Dylan manual, so i don't know if this is possible.

Unboxed vectors would be a big win for small datatypes. At the moment the
only types for which this has been defined are char and unicode-char; a new
subclass of vector which only allowed objects from a single class to be stored
in it would be a big win.

Incidentally, whilst we're on the subject of types; unless I'm missing
something, Dylan doesn't seem to have an equivalent to Common Lisp's
'the'; I guess this can be simulated by having a macro wrap a bind around the
expression, but it'd be nice to have something semi-standard. 

Simon