This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 115d. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-10-26

1752. Right-recursion in mem-initializer-list

[Moved to DR at the November, 2014 meeting.]

The grammar for mem-initializer-list in 11.9.3 [class.base.init] paragraph 1 (after the resolution of issue 1649) is right-recursive:

mem-initializer-list:
mem-initializer ..._opt
mem-initializer ..._opt , mem-initializer-list

In general, however, such lists elsewhere in the Standard are described using a left-recursive grammar, e.g., for initializer-list in 9.4 [dcl.init] paragraph 1:

initializer-list:
initializer-clause ..._opt
initializer-list , initializer-clause ..._opt

It would be better to be consistent in the definition of mem-initializer-list.

Proposed resolution (February, 2014):

Change the grammar in 11.9.3 [class.base.init] paragraph 1 as follows:

mem-initializer-list:
mem-initializer ..._opt
mem-initializer-list , mem-initializer ..._opt , mem-initializer-list