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Re: [Scheme-reports] Padding/placeholders (hashes) in numerical syntax
On Mon, Sep 05, 2011 at 01:54:12PM -0400, Aubrey Jaffer wrote:
> | Date: Mon, 5 Sep 2011 18:57:16 +0200
> | From: Peter Bex <Peter.Bex@x>
> | On Sun, Sep 04, 2011 at 09:12:42PM -0400, Aubrey Jaffer wrote:
> | > I believe that R5RS permits engineering-notation.
> | Absolutely; I was wondering how it decides to print 3/4 as 750.0e-3
> | considering 7.5e-1 is equally acceptable, as is 0.75 or 75e-2 or
> | any other exponent prefixed by a suitably scaled number.
> In engineering-notation the exponent is always an integer multiple of
> 3. SCM scales the matissa to be between 1 and 1000, and omits the
> exponent when it is 0.
I see. I've now added support for this kind of notation to the tests,
and I've also added a mode in which it accepts fractional numbers being
parsed into flonums, like the version of SCM which I have (a horribly
outdated version 5e3) seems to do. Chicken without the "numbers" egg
does this as well.
Most failing tests in SCM are about NaN/Inf syntax and padding now;
27 errors with 5e3. I'm sure the newer version has less errors.
"The process of preparing programs for a digital computer
is especially attractive, not only because it can be economically
and scientifically rewarding, but also because it can be an aesthetic
experience much like composing poetry or music."
-- Donald Knuth
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