Assign to interface array initializator compiles but why?

Question

Today I was thinking it would be neat to make anonymous object which is type of some interface, and I have seen on SO that I am not only one.

Before I started checki

Answer 1

it would be neat to make anonymous object which is type of some interface,

I know there is no way to do anonymous objects implement interface, but I have not seen complaint from VS about this code.

The problem is, you're assuming that the following code creates a new instance of an anonymous type

new Holder { someInterface = { Property = 1 } };

{ Property = 1 } does not create a new instance of an anonymous type - this is an object initializer.

If you do replace your code with a proper instantiation of an anonymous type, then the compiler will complain that the instance cannot be implicitly converted to ISomeInterface, like you expected.

new Holder { someInterface = new { Property = 1 } };