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cconstantsdeclarationfunction-signature

What's the meaning of multiple const qualifiers?

Code:

const char* const* const* foo(int bar);

I've seen double consts before which prevent the modification of the pointer too. First time i've seen triple const in my life. Wondering what its use is.

Solution

  • In your example all but the top level of indirection all const qualified.

    const char            /* const qualified base level */
    *const            /* const qualified level 1 */
    *const            /* const qualified level 2 */
    *                 /* regular level 3 */
    foo(int bar);

    foo is a function that accepts an int argument and returns a regular pointer.
    The pointer it returns points to a const qualified pointer
    which, in turn, points to another const qualified pointer
    which points to const qualified char