[temp.dep.expr] (original) (raw)
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 formx.yorxp->ythe type of the expression is usually the type of the memberyof the class ofx(or the class pointed to byxp).
However, ifxorxprefers to a dependent type that is not the current instantiation, the type ofyis always dependent.
Ifxor xprefers to a non-dependent type or refers to the current instantiation, the type ofyis the type of the class member access expression.
— _end note_]