Re: How to handle operator of undefined associativity

BGB / cr88192 <cr88192@hotmail.com> wrote:
(snip)


> I guess I will add here that associativity only really makes
> sense when binary operators are in use:
> "3+4*5" => "(3+4)*5" or "3+(4*5)", ...


> but, with a unary operator, there is only a single possible parsing:
> the operator and the expression it operates on.


That is true if you allow only prefix operators, or only
postfix operators, but not if you allow both. Consider C:


      *x++ is *(x++) or (*x)++


Where * and ++ are both unary operators.


> one can't have associativity directly between the operators,
> as this would not make sense:
> "! ! ! x" => "(! !) ! x;"? nope...


Traditionally, Fortran didn't allow two operators next to each
other without parenthesis. It might be that the rules have changed
some over the years, but I believe that you still can't say


        .NOT..NOT..NOT.X


-- glen
[This isn't associativity, it's precedence. Humph. -John]

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