never seen a type *fnc (params); before, need clarification on use

This is a discussion on never seen a type *fnc (params); before, need clarification on use within the C++ Programming forums, part of the General Programming Boards category; I've never seen something like: Code: class IdClass { public: IdClass(); // initialize the list ~IdClass(); // de-allocate the list ...

  1. #1
    Registered User daluu's Avatar
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    never seen a type *fnc (params); before, need clarification on use

    I've never seen something like:
    Code:
    class IdClass {
      public:
        IdClass();			// initialize the list
        ~IdClass();			// de-allocate the list
    
        void Add (void *item, int Key);	// Put item into list
        void *Remove (int Key);
      private:
        IdElement *first;  	// Head of the list, NULL if list is empty
        IdElement *last;		// Last element of list
    };
    
    void * IdClass::Remove (int a)
    {
      IdElement * tmp = first, * prev = (IdElement *)NULL;
      while ((tmp != NULL) && (tmp->key != a))
      {
        prev = tmp;
        tmp = tmp->next;
      }
      //more code in function here
      return value;
    }
    How do I use the Remove function if I'm instantiating an instance like this:
    Code:
    IdClass *test;
    test = new IdClass();
    
    //for add I can do this
    test->Add(itemptr,5);
    I don't know how to call Remove. I've never seen that syntax before. And what does that syntax mean?

  2. #2
    ~viaxd() viaxd's Avatar
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    void *Remove (int Key);
    a function that takes an int and returns a void pointer. in c++ you need to cast the return value to the needed type, i think, not sure
    :wq

  3. #3
    Registered User
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    Code:
    int main()
    {
      ....
      test.Remove(5);
      ....
    }
    >>I've never seen that syntax before. And what does that syntax mean?

    what part of the which syntax don't you understand?

  4. #4
    Registered User daluu's Avatar
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    thanks for the info. and from that info, if "test" was not a pointer to the instance but rather the instance itself, the call to Remove would be

    Code:
    test->Remove(5);
    right?

    I didn't realize the function was returning a pointer of the type, so I didn't know what was the purpose of defining the function that way. Now I know. thanks.
    Last edited by daluu; 12-02-2004 at 12:21 PM.

  5. #5
    Registered User
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    My bad.

    test.Remove(5); if test is an object and
    test->Remove(5); if test is a pointer to an object.

    Sorry. Didn't register in my noggin that test was declared dynamicaly

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