What is a punctuation character?

Gabriel Dos Reis gdr at integrable-solutions.net
Fri Mar 16 19:30:58 CET 2012


On Fri, Mar 16, 2012 at 1:18 PM, Brandon Allbery <allbery.b at gmail.com> wrote:
> On Fri, Mar 16, 2012 at 14:08, Gabriel Dos Reis
> <gdr at integrable-solutions.net> wrote:
>>
>> The lexical structure chapter defines the non-terminal uniSymbol as
>>
>>     uniSymbol ::= any Unicode symbol or punctuation
>>
>> There is a slight ambiguity here: is that description supposed to
>> be parsed as:
>>   (a) "Unicode (symbol or punctuation)", or
>>   (b) "(Unicode symbol) or punctuation"?
>
>
> (a) and I thought the report specified that the language's lexemes are
> defined in terms of Unicode properties so (a) is the only meaningful
> interpretation.  (b) is not particularly meaningful, as your own question
> demonstrates.

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?

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.

-- Gaby



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