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Re: [Scheme-reports] 7.1.1 lexical structure

Three hours ago, John Cowan wrote:
> Andy Wingo scripsit:
> > WHITESPACE is specified as SPACE OR NEWLINE.  Should TAB be included?
> > LF?  Some unicode category?
> I don't think so.

Yet another step back from R6RS, that fixed the weak BNF in r5rs.  The
step is back to a vague comment:

  Whitespace characters are spaces and newlines.  (Implementations
  typically provide additional whitespace characters such as tab or
  page break.)

that is not part of the BNF.  So given that the BNF is the minimal
requirement, and the usual "unspecified" for anything else, it looks

  (length '(foo<tab>bar))

can (and usually will) return 2, but sometimes it will return 1, and
sometimes it will set your grandmother on fire.

> Schemers don't use hard tabs anyway,

That's a very odd and easily refuted statement.

But worse, it continues with the apparent R7RS tradition of zigzaging
around motivations and principles -- when you feel like it, you cite
the charter as the holy bible that rates r5rs then ieee and then r6rs,
and other times a srfi becomes good enough of a reason for a change;
sometimes backward compatibility is so important that it seems that
breaking it is risking some r7rs jihad and/or hunger strikes, and
other times it settles with some poor "don't use hard tabs anyway"

But yeah, discussions are futile, because "if you want R6RS, you know
where to find it".  Or better: "there's no point in moaning about it

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!

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