FW: Haskell 98 report problem re lexical structure.

Christian Sievers sievers@ips.cs.tu-bs.de
Wed, 25 Jul 2001 17:57:59 +0200 (MET DST)


Simon Peyton-Jones proposed:

> 1.  I will use "lexeme" consistently to mean what the "lexeme"
> production means.
That's good.

> 2.  The place that "lexeme" is currently used inconsistently is in 2.3
> (Comments)  Here I propose to replace paras 2 and 3 thus:
>  
> "An ordinary comment begins with a sequence of two or more consecutive
> dashes (e.g. --) and extends to the following newline. The sequence of
> dashes must not be the prefix of a legal lexeme. For example,

Any number of dashes is a prefix of a legal lexeme.
You want to talk about what follows, but this formulation is about
what might follow. (Or at least, that's how I understand it.)
How about something like:
The sequence of dashes must not be followed by another symbol,
for example --> or --| do not begin a comment, they are just ordinary
lexemes.

> 5.  [Re Christian S's proposal, which I sent earlier, remove "opencom"
> from "lexeme"]

That is consisted with the other change you suggested in 2., and
indeed a nicer way to be so.


The second sentence in 5.5.1 reads
Since qualifier names are part of the lexical syntax, no spaces are
allowed between the qualifier and the name.

I think this should be
Since qualified names...
              ^
and could as well be
Since qualified names are lexemes, no spaces are allowed...


All the best
Christian Sievers