Objective C const NSString * vs NSString * const
Solution 1:
It's not the same. The const modifier can be applied to the value, or the pointer to the value.
int * const
A constant pointer (not modifiable) to an integer (its value can be modified)
const int *
A modifiable pointer to a constant integer (its value can't be modified)
So you can imagine:
const int * const;
Solution 2:
Constant pointer is NOT a pointer to constant. Constant pointer means the pointer is constant. E.g. constant pointer int * const ptr2;
indicates that ptr2
is a pointer which is constant. This means that ptr2
cannot be made to point to another integer. However, the integer pointed by ptr2
can be changed.
Whereas a pointer to constant const int * ptr1;
indicates that ptr1
is a pointer that points to a constant integer. The integer is constant and cannot be changed. However, the pointer ptr1
can be made to point to some other integer.