On Sat, 13 Aug 2016 16:28:57 +0000, deadalnix wrote:
> C# use generic (aka type erasure) for objects
Incorrect:
---
public class Foo {}
var fooList = new List<Foo>();
var objectList = (List<object>)(object)fooList;
---
This throws InvalidCastException. Which isn't possible with type erasure.
The equivalent Java code will not throw an exception because, after type
checking, List<T> is converted to List<Object>. That's the definition of
type erasure.
Similarly, you can inspect the methods on List<Foo> at runtime in C# and
see that, for instance, the `Add` method takes a parameter of type Foo.
And you can look at the type of `fooList` with reflection and see that
it's List with generic parameter 0 set to Foo. That's stuff you can't do
with type erasure.
The code that .NET generates for a generic instantiation with class type
is different from the code it generates for a generic instantiation for a
struct simply because structs are not like classes.
