This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 112e. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.
[Accepted at the July, 2022 meeting.]
The specification about the relative sequencing of multiple parameters of the subscripting operator is missing. Also, issue 2507 adds support for default arguments for user-defined subscripting operators, but the sequencing of these is unspecified, too.
Suggested resolution: [SUPERSEDED]
Add a new paragraph 4 at the end of 220.127.116.11 [expr.sub]:
Notes from the 2022-05-20 CWG telecon:
A wording approach amending 18.104.22.168 [over.match.oper] paragraph 2 instead would be preferred.
Possible resolution (2022-05-21): [SUPERSEDED]
Change in 22.214.171.124 [over.match.oper] paragraph 2 as follows:
Therefore, the operator notation is first transformed to the equivalent function-call notation as summarized in Table 17 (where @ denotes one of the operators covered in the specified subclause). However, the operands are sequenced in the order prescribed for the built-in operator (7.6 [expr.compound]).
Notes from the 2022-06-03 CWG telecon:
Repeating the function call rules for the subscript operator in 126.96.36.199 [expr.sub] instead would be preferred, to avoid any impression of a special case.
Proposed resolution (2022-06-24, amended 2022-07-15, approved by CWG 2022-07-15):
Change in 188.8.131.52 [expr.sub] paragraph 1 as follows:
A subscript expression is a postfix expression followed by square brackets containing a possibly empty, comma-separated list of initializer-clauses
whichconstitute the arguments to the subscript operator. The postfix-expression is sequenced before each expression in the expression-list .