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
[Accepted at the February, 2022 meeting.]
Presumably the following example is intended to be ill-formed:
struct A {
(*operator int*());
};
A a;
int *x = a; // Ok?
It is not clear, however, which rule is supposed to reject such a member-declaration.
Proposed resolution (December, 2021):
Change 11.4.8.3 [class.conv.fct] paragraph 1 as follows, splitting the paragraph as indicated:
A member function of a class X with a name of the formconversion-function-id:
operator conversion-type-id
conversion-type-id:
type-specifier-seq conversion-declaratoropt
conversion-declarator:
ptr-operator conversion-declaratoropt
A declaration whose declarator-id has an unqualified-id that is a conversion-function-id declares a conversion function; its declarator shall be a function declarator (9.3.4.6 [dcl.fct]) of the form
ptr-declarator ( parameter-declaration-clause ) cv-qualifier-seqopt
ref-qualifier-seqopt noexcept-specifieropt attribute-specifier-seqopt
where the ptr-declarator consists solely of an id-expression, an optional attribute-specifier-seq, and optional surrounding parentheses, and the id-expression has one of the following forms:
in a member-declaration that belongs to the member-specification of a class or class template but is not a friend declaration (11.8.4 [class.friend]), the id-expression is a conversion-function-id;
otherwise, the id-expression is a qualified-id whose unqualified-id is a conversion-function-id.
A conversion function shall have no parameters and shall be a non-static member function of a class or class template X; it specifies a conversion from X to the type specified by the conversion-type-id, interpreted as a type-id (9.3.2 [dcl.name]).
Such functions are called conversion functions.A decl-specifier in the decl-specifier-seq of a conversion function (if any) shall not be
neithera defining-type-specifiernor static. The type of the conversion function(9.3.4.6 [dcl.fct])is “noexceptopt function taking no parameter cv-qualifier-seqopt ref-qualifieropt returning conversion-type-id”.A conversion function is never used to convert a (possibly cv-qualified) object to the (possibly cv-qualified) same object type (or a reference to it), to a (possibly cv-qualified) base class of that type (or a reference to it), or to cv void.102 [Example 1:...