do we need both of these?
if we have both, they should share code.

     -- ../../m2/enginering.m2:519
     Ring _ Symbol := RingElement => (x,s) -> x.indexSymbols#s
     ---------------------------------
     -- code for method: Symbol _ Ring
     -- ../../m2/ofcm.m2:141-144
     Symbol _ Ring := RingElement => (x,M) -> (
          if M.?indexSymbols and M.indexSymbols#?x then M.indexSymbols#x
          else error "symbol not found in ring"
          )
