13 Templates [temp]

13.8 Name resolution [temp.res]

13.8.3 Dependent names [temp.dep]

13.8.3.3 Type-dependent expressions [temp.dep.expr]

Except as described below, an expression is type-dependent if any subexpression is type-dependent.
this is type-dependent if the class type of the enclosing member function is dependent ([temp.dep.type]).
An id-expression is type-dependent if it is not a concept-id and it contains or if it names a dependent member of the current instantiation that is a static data member of type “array of unknown bound of T” for some T ([temp.static]).
Expressions of the following forms are type-dependent only if the type specified by the type-id, simple-type-specifier or new-type-id is dependent, even if any subexpression is type-dependent:
simple-type-specifier ( expression-list )
:: new new-placement new-type-id new-initializer
:: new new-placement ( type-id ) new-initializer
dynamic_­cast < type-id > ( expression )
static_­cast < type-id > ( expression )
const_­cast < type-id > ( expression )
reinterpret_­cast < type-id > ( expression )
( type-id ) cast-expression
Expressions of the following forms are never type-dependent (because the type of the expression cannot be dependent):
literal
sizeof unary-expression
sizeof ( type-id )
sizeof ... ( identifier )
alignof ( type-id )
typeid ( expression )
typeid ( type-id )
:: delete cast-expression
:: delete [ ] cast-expression
throw assignment-expression
noexcept ( expression )
[Note 1:
For the standard library macro offsetof, see [support.types].
— end note]
A class member access expression is type-dependent if the expression refers to a member of the current instantiation and the type of the referenced member is dependent, or the class member access expression refers to a member of an unknown specialization.
[Note 2:
In an expression of the form x.y or xp->y the type of the expression is usually the type of the member y of the class of x (or the class pointed to by xp).
However, if x or xp refers to a dependent type that is not the current instantiation, the type of y is always dependent.
If x or xp refers to a non-dependent type or refers to the current instantiation, the type of y is the type of the class member access expression.
— end note]
A braced-init-list is type-dependent if any element is type-dependent or is a pack expansion.
A fold-expression is type-dependent.