CODEWITHSUNDEEP
c#var
Kapol
Kapol

Reputation: 6463

Can you take advantage of implicit type variables with a class named `var`?

I just found out that it is possible to use the keyword var as a class name:

public class var // no problem here
{
}

Now if I overload the implicit cast operator I can use my class in an interesting manner:

namespace MyApp
{
    class Program
    {
        static void Main(string[] args)
        {
            var x = 1; // var is of type MyApp.var
        }
    }

    public class var
    {
       public implicit operator var(int i)
       {
           return new var();
       }
    }
}

In such scenario, is it still possible to somehow make the compiler infer the types? This blog entry states that it is not possible (go to the paragraph starting with "Or, another example."), but maybe something changed since 2009?

Upvotes: 7

Views: 260

Answers (1)

Kapol
Kapol

Reputation: 6463

To make it short

It is not possible to use implicit variable declaration if you name a class var.

Can't the C# design team just disallow naming classes like that to avoid confusing code?

No, because that might break some code written before the new meaning of var was introduced in the language. All legacy code with var as class names would not compile anymore. And I read lately that backwards compatibility is very important for the C# designer team.

Upvotes: 2

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