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From: Ian Collins <ian-news@hotmail.com>
Newsgroups: comp.lang.c++
Subject: Re: " *first = new string(*rhs.first);" cannot compile in MSVC
Date: Thu, 12 Jan 2012 18:04:42 +1300
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On 01/12/12 04:29 PM, fl wrote:
> On Jan 11, 9:31 pm, Ian Collins<ian-n...@hotmail.com>  wrote:
>> On 01/12/12 03:22 PM, fl wrote:
>>
>>
>>
>>
>>
>>> Hi,
>>> I am learning C++ with a web download small C++ routine. The member
>>> function below the dot line cannot compile in MSVC express 2010. The
>>> error message is:
>>
>>> 1>c:\users\jeff\documents\visual studio 2010\projects\ldpc\person
>>> \person.cpp(27): error C2679: binary '=' : no operator found which
>>> takes a right-hand operand of type 'std::string *' (or there is no
>>> acceptable conversion)
>>
>>> Because the web site is a university C++ course, I guess it should not
>>> be a totally wrong. I also feel that line 27 usage is really strange.
>>
>>> What is your opinion? Thanks a lot.
>>
>>> ....................
>>
>>> const Person&    Person::operator=(const Person&    rhs){
>>>     if( this !=&rhs ){
>>>       delete first;
>>>       delete last;
>>> (line 27):    *first = new string(*rhs.first);
>>>       *last = new string(*rhs.last);
>>>       id = rhs.id;
>>>     }
>>
>>>     return *this;
>>> }
>>
>> The definition of Person would help (what are first and last?).
>
> Thank you very much. Here is the Person definition file:
>
> //http://www.cs.middlebury.edu/~dkauchak/classes/s10/cs062-s10/
> problems/destructor
> ...........
> #ifndef PERSON_H
> #define PERSON_H
>
> #include<string>
>
> using namespace std;

Don't ever put this in a header!

> class Person{
>   public:
>    Person(const string&  first, const string&  last, int id);
>    Person::Person(const Person&  rhs);
>    const Person&  Person::operator=(const Person&  rhs);
>    string getFirst() const;
>    string getLast() const;
>    void setLast(const string&  newLast);
>    int getId() const;
>    string toString() const;
>
>   private:
>    string* first;
>    string* last;
>    int id;
> };
>
> #endif

So your original code is attempting to assign a std::string* to a 
std::string.


As Alf suggests, don't use pointers.

-- 
Ian Collins