William D Clinger scripsit:
> The solution I recommend is to change the first production of
> <delimiter> to <whitespace>.
+1
> Treating #!r6rs as a delimiter, but not #!r5rs or #!fold-case, is
> especially confusing.
I agree. All things of the form #!quodlibet should be treated
identically.
> I recommend the addition of # to the list of delimiters. This might
> cause problems for backwards compatibility, however, since several
> systems have been allowing # as a <subsequent>.
And even as an initial, in the case of Chicken.
> Since there are over 235,000 Unicode characters that can begin an R6RS
> identifier, programmers are likely to assume that identifiers can begin
> with any alphabetic character. With the current draft, however, 163
> alphabetic characters (of Unicode 5.0.0) cannot begin an identifier.
> This should be fixed.
In fact, those 163 characters are all Unicode combining marks, which
should never appear at the beginning of an identifier. So the status
quo should be retained.
> Either remove the -> wart from the lexical syntax,
+1
> I think it is time to drop the # notation for insignificant digits.
+1
> The #\nul, #\esc, and #\delete characters have no corresponding
> two-letter escape sequence in strings, while the other eight named
> characters do. This seems arbitrary and capricious.
IMHO, #\nul should get \0, #\esc should get \e, and #\delete should
be dropped.
> The formal syntax is ambiguous, which implies it is not LR. This
> creates unnecessary obstacles to the use of some standard scanner and
> parser generators. The ambiguities I have noticed so far include:
[examples snipped]
+1
--
John Cowan http://ccil.org/~cowan cowan at ccil.org
Lope de Vega: "It wonders me I can speak at all. Some caitiff rogue did
rudely yerk me on the knob, wherefrom my wits still wander."
An Englishman: "Ay, a filchman to the nab betimes 'll leave a man
crank for a spell." --Harry Turtledove, Ruled Britannia
Received on Sat Jun 23 2007 - 01:42:51 UTC