Multimethods in C# 4.0 with 'dynamic'

re: Multimethods in C# 4.0 with 'dynamic'

Nate — Wed, 27 Oct 2010 22:24:01 GMT

nikitazu - What you're missing is that the implementation methods are named CollideWithImpl, not CollideWith. If all of the methods had the same name then you would be correct. However, there is only one CollideWith method and it's defined for the base class Thing.

re: Multimethods in C# 4.0 with 'dynamic'

nikitazu — Sat, 09 Jan 2010 22:28:16 GMT

Correct me if I'm wrong, but is it really a dynamic dispatch?

in this example:

var asteroid = new Asteroid();

var spaceship = new Spaceship();

CollideWith(asteroid, spaceship);

CollideWith(spaceship, spaceship);

overloads

CollideWith(Asteroid x, Spaceship y)

CollideWith(Spaceship x, Spaceship y)

are called directly, and

CollideWith(Thing x, Thing y)

is never invoked

re: Multimethods in C# 4.0 with 'dynamic'

Laurion Burchall — Fri, 21 Aug 2009 21:54:22 GMT

Good point about the recursion. Using the same name is cute, but can easily lead to those problems. (Making Thing abstract would prevent this specific problem but leave the door open for future occurences).

re: Multimethods in C# 4.0 with 'dynamic'

richard_deeming — Wed, 19 Aug 2009 17:43:30 GMT

Nice - but wouldn't it be better to use a different method name to avoid infinite recursion?

var x = new Thing();

var y = new Thing();

CollideWith(x, y);

or:

var x = new Asteroid();

var y = new Thing();

CollideWith(x, y);