Well, I was asking, so I can't really tell :)
But SRFI-70 is supposed to be specifically designed to "improve" on R5RS, whether we/I agree or not that it is an improvement. The point is that Gambit is extending R5RS, even implementing some of the funcionality that R6RS specified (like flonum/fixnum operations).
To be honest, I really don't get the difference between inexact/flonum exact/fixnum in Gambit. Documentation is not very extense on this topic, as far as I can tell the same operations apply to inexact/flonum, ditto exact/fixnum. But I think that if you are going to produce numeric code in Gambit, understanding this topic well enough is key.
SRFI-70 "redefines" R5RS number section (6.2). It modifies these areas (quoted from the SRFI):
* incorporates an inexact real positive infinity and an inexact real negative infinity (Gambit implements this)
* extends number syntax to incorporate inexact real infinities, (Gambit implements this)
adapts Common-Lisp semantics for `expt' and extends them to include inexact real infinities,
corrects the description of `sqrt',
sharpens the distinction between exact and inexact numbers
removes a contradiction related to exactness,
extends `gcd' and `lcm' to exact rational numbers,
extends `quotient', `modulo', and `remainder' to finite real numbers,
clarifies the behavior of `inexact->exact' applied to an exact argument,
clarifies the behavior of `exact->inexact' applied to an inexact argument,
adds convenience procedures `exact-round', `exact-ceiling', `exact-floor', and `exact-truncate',
These topics, specially for numerical methods implementation, seem to me as topics to understand well. Now, I don's say SRFI-70 proposal is better than R5RS, but I'd like to know what "standard" follows Gambit, to work under those premises.
Thank you very much,
Best regards