Re: rfc: pow-operator

On Sun, Nov 24, 2013 at 7:58 AM, Tjerk Meesters <tjerk.meesters@gmail.com>wrote: > On Sun, Nov 24, 2013 at 8:31 AM, Kris Craig <kris.craig@gmail.com> wrote: > > > We should be following standard Order of Operations here. As such, the > > option of no associativity should be included. Furthermore, there needs > to > > be a voting option regarding how to deal with even exponents of negative > > bases; i.e. treat "-3 ^ 2" as "-3 ^ 2 == 9" or as "-(3 ^ 2) == > > -9". > > > > To support the latter "-3 ** 2 == 9" we would require a unary minus that > has a higher precedence than the exponent operator and as such falls > outside of the scope of this RFC. > > That said, I'm not even sure whether we can support a unary minus with the > current parser. > Huh? We already support a unary minus with the current parser. It has the same precedence and associativity as ++ (%prec). You can adjust the relative precedence of ** and - by adjusting the relative precedence of ** and T_INC (or making it completely independent if you like.) Nikita