In c++std-core-14770, Dos Reis suggests that operator[] and operator() should both be allowed to be static. In addition to that, he suggests that both should allow multiple parameters. It's well known that there's a possibility that this breaks existing code (foo[1,2] is valid, the thing in brackets is a comma-expression) but there are possibilities to fix such cases (by requiring parens if a comma-expression is desired). EWG should discuss whether such unification is to be strived for.

Discussed in Rapperswil 2014. EWG points out that there are more issues to consider here, in terms of other operators, motivations, connections with captureless lambdas, who knows what else, so an analysis paper is requested.