Modifying Member Variables Inside const Member Functions

Modifying Member Variables Inside const Member Functions

Declaring a member variable as mutable is not the only way to mark it as modifiable within a constant member function. It is actually not really good practice to mark a member variable as mutable because this allows all const member functions to modify this member variable.

The compiler invisibly passes this pointer (Class X* this) to every member function, while, in the case of the constant member function, the compiler passes this pointer (const X* this).

The immutability of this pointer can be casted away using const_cast and then used for modifying any member vaiable required. Here’s an example:

void X::ConstMemberFunc() const{	X *ptr = const_cast(this);		ptr->....}
See also  Essential Measures for Safeguarding Your Digital Data

About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

About Our Journalist