Re: [q-lang-users] New stuff in cvs: multichar ops, views

[Rob H. <hub...@gm...>]

On 31/05/07, Albert Graef <Dr....@t-...> wrote:
> > Rob Hubbard wrote:
> >> It seems that now, introducing a new symbol will affect the way that
> >> code is parsed. This is something I find a little worrying.
> >
> > You're right. Right now the lexer inspects the symbol table to partition
> > punctuation symbols. I agree that this is a bad idea since it makes the
> > syntax depend on the declared operator symbols. I will fix that right
> > away.
>
> Well, it sounded like a good idea, but actually it isn't. ...

Shame, but I agree with your decision, given the problems you
described, that the breakage would after all be too severe and the
resulting behaviour too inconvenient.

Thanks too for all the (attached) detail about symbol parsing.

I wonder whether there's any scope for Q itself to issue warnings
about some or all punctuational operator declarations. This might not
be too 'noisy' if only one such warning was given. Then again, perhaps
this isn't such a good suggestion.

Alternatively, is there any way of issuing a warning if the lexer's
action is affected by the presence of an operator definition when
parsing a sequence of punctuation characters to form a symbol? Again,
probably not, as I can't see a good rule or heuristic to distinguish
likely intended parses from unintended ones...

Rob.