What is a punctuation character?

Brandon Allbery allbery.b at gmail.com
Fri Mar 16 19:49:41 CET 2012

On Fri, Mar 16, 2012 at 14:30, Gabriel Dos Reis <
gdr at integrable-solutions.net> wrote:

> It is not clear what "the language's lexemes are defined in terms of
> Unicode properties"
> really means.  Why would you need ascSmall (and similar ASCII
> character categories) then
> when you already have uniSmall and associates?

I have to assume that is a leftover from an earlier version of the report,
because it is indeed already included.

See in section 2.1:

"Haskell uses the Unicode
character set. However, source programs are currently biased toward the
ASCII character set used in earlier versions of Haskell."

I understand this to indicate that Unicode character classes are intended,
and it does indeed hint that references to ASCII are references to older
versions of the language (and should probably be considered fossils, as
ASCII itself is; the American Standard Code for Information Interchange was
obsoleted by ISO 8859, and modern references to "ASCII" usually should be
taken to mean "ISO 8859/1").

> It is not clear that (b) is all that "not particularly meaningful".
> Have a look at the production
> <symbol>: it excludes double quote(") and apostrophe (') from uniSymbol.

The notion of "symbol with certain lexicals that have other meanings *that
are specified elsewhere in the report*" is not precise enough?  It may be
difficult to characterize things with your required precision, since every
general statement will necessarily have to carry part or potentially all of
the entire Report within it if it is not sufficient to use the statement's
context (as describing some part of the Report).

brandon s allbery                                      allbery.b at gmail.com
wandering unix systems administrator (available)     (412) 475-9364 vm/sms
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