c++ const member function that returns a const pointer.. But what type of const is the returned pointer? -

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i apologize if has been asked, how create member function in c++ returns pointer in following scenerios: 1. returned pointer constant, junk inside can modified. 2. junk inside constant returned pointer can modified. 3. neither junk, nor pointer can modified.

is so:

  1. int *const func() const
  2. const int* func() const
  3. const int * const func() const

all of tutorials i've read don't cover distinction.

side note: if method declared const tutorials i'm stating won't modify parameters.. not clear enough me in case when parameter pointer. parameters need like:

a. void func(const int* const x) const;
b. void func(const int* x) const;
c. void func(const int* const x) const;

i don't know book have read, if mark method const means this of type const myclass* instead of myclass*, in turn means cannot change nonstatic data members not declared mutable, nor can call non-const methods on this.

now return value.

1 . int * const func () const

the function constant, , returned pointer constant 'junk inside' can modified. however, see no point in returning const pointer because ultimate function call rvalue, , rvalues of non-class type cannot const, meaning const ignored anyway

2 . const int* func () const

this useful thing. "junk inside" cannot modified

3 . const int * const func() const

semantically same 2, due reasons in 1.

hth


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