[C/C++] Why I can't assign a constant char pointer to a char pointer?

Question

Hey Community,

just started learning C++ 2 days ago, but already have much experience with ANSI-C.
Although I don’t learning programming with this plattform, I use it to ask some questions ;)

My problem now is the following, let me show this shortened code snipped:

class Entity{
private:
char* name;
public:
Entity(const char* name1){
name = name1;
}
}

int main(){
Entity person("Steve");
}

But this doesn’t work, because I can’t assign "Steve" which is a (constant) chain of chars to Entity::name which holds a pointer of a char. So I must declare Entity::name as a constant or assign it with a defined range. But that don’t make sense for me.
I mean, the string "Steve" is lying somewhere in the memory, so I should pointing to it. But no.
Sorry if this is a bit unclear, german is my mother tongue.

Answer 1

Your problem is when you do name = name1.
name1 is const char* and name is char* and the compiler will tell you that const char* cannot be converted to char*.

The reason the conversion cannot be done is because by saying const, you say that the variable will not change but then you put it in a type that can be modified.

One solution in your case is to change the type of name to const char*

Answer 2

You simply forgot a const!
The constructor is ok ..
But not the member storing the literal, otherwise you can try to modify a literal through Entity::name which is UB or probably illegal

private :
CONST char* name;

Now you have to modify also the constructor to
Entity(const char* n):name(n){}

Answer 3

I would think about what the benefit is to trying to make your argument const. Is it worth the effort to try to work around that? Personally, I don't think so. I also think that if you are going to be programming in C++, try using string types. char pointers is more of a C thing.

You could also try using a const pointer instead of a pointer to a const char:

Entity(char* const name1)

I'm not sure that is what you are going for, but I figured that I would mention it.

Note that const char* name1 is the same as char const *name1, just as a weird piece of trivia.