~ patterns

[Ian Lynagh]

On Fri, Feb 03, 2006 at 09:54:59AM +1100, Patryk Zadarnowski wrote:
> On 03/02/2006, at 9:25 AM, Wolfgang Jeltsch wrote:
> 
> >Am Mittwoch, 1. Februar 2006 01:32 schrieb Patryk Zadarnowski:
> >>[...]
> >
> >>The proposal would be to remove the unary "-" altogether, and,  
> >>instead,
> >>extend the lexical syntax of numeric constant to allow "+" and "-"  
> >>prefix.
> >
> >Would this mean that (-x) is a section while (-1) isn't?  That  
> >would be
> >confusing.
> >
> >Apart from this, I would like to see the only unary operator of  
> >Haskell
> >removed.
> 
> Yes, it *would* mean that (-x) and (- 1) are sections while (-1)  
> isn't, and
> yes, that would be slightly confusing (and a good compiler might want to
> issue a warning whenever it sees a construct of the form (-identifier).

I'd much prefer it gave a warning for (-1) as, with -1 being a single
lexeme, parentheses would never be needed.

> In both cases, accidentally omitting a space will result in a  
> compiler or type error
> anyway, since (-x) has a different type than (- x), so such accidents  

Do you mean (-1) and (- 1) here?


Thanks
Ian, in support of this proposal