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Re: [Scheme-reports] Numerical example (real? -2.5+0.0i)

Aubrey Jaffer scripsit:

> R5RS also uses the term "general real number"; and this is
> problematical.  The finite real values encoded in floating-point
> representations are all rational, so there are no "non-rational real
> number"s in implementations using fixed-point and floating-point
> representations.

That's gone.  In R3RS it said simply "real number", and when someone
noticed that was wrong, it was wrongly changed to "general real number".
The context is the trig functions, and it should say "inexact number".

> The terms integer, rational, real, and complex are too few to
> adequately describe all the possible numeric Scheme types.

No finite, or indeed countably infinite, set of names can identify all
the numeric types.  Scheme provides a few that may be useful.  Given the
issue around 0.0 (which may be zero or a small number), I'm proposing
that R7RS provide two versions, one which follows R5RS and one which
follows R6RS, using the R6RS names (*-valued) for the R5RS versions.

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wise wives welcome the spring           cowan@x
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