[racket-dev] flonum vs. inexact-real

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sun Oct 3 07:41:41 EDT 2010

At Sat, 02 Oct 2010 17:12:20 -0600, Neil Toronto wrote:
> @Matthew: is there a problem with declaring "float" to mean 
> "platform-dependent floating-point format?" Embedded devices don't 
> always easily support 64 bits, and I'd hate to be stuck with 64 if 
> 128-bit floats become ubiquitous.

I think we could sensibly define "flonum" that way. That convention
would be similar to "fixnum", in that the values vary among platforms.
Unlike fixnums, you could get different results from generic arithmetic
on "flonums" when using different platforms, but maybe that's all part
of the floating-point trade-off.

If "flonum" becomes 128-bit doubles, then we may end up wanting 64-bit
doubles for the same reasons that we might want 32-bit floats now. So,
that suggests again that "flonum" should be more specific than "inexact

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