Question

I’m playing with operator overloading in C++, specifically the assignment operator “=”.

So, at a time, I’m able to do this:

MyClass var1;
var1 = "string";

But, it gives me an error when I try to do this:

MyClass var2 = "string";

Somebody knows why? And how can I make it possible?

Answer 1

The second example isn’t calling operator=, it’s calling a conversion constructor for const char [], or whatever you’d be using it for internally, as long as it can convert from that (e.g. std::string), which doesn’t exist as of yet. You can see one implemented in std”OrgnlDave’s answer. It’s almost identical to

MyClass var2 ("string");

The latter, though, is explicit, whereas the former is implicit. To see the difference, make a constructor and mark it explicit. The code here will work, but yours won’t. This can save confusion when you, for example, pass a string by accident instead of a MyClass, and it gets implicitly converted when it isn’t even meant to be a MyClass in the first place.