[External] : Re: Proposal: java.lang.runtime.Carrier

[Brian Goetz]

> Adding more information,
> we want the carrier to be a primitive type (to be able to optimize it 
> away), which means that we can not use null to represent "do_not_match",
> we have to have a flag inside the carrier for that.

The alternate approach is to use a .ref class for partial patterns 
(using null for "no match") and a B3 class for total patterns (since it 
needs no failure channel.)

I think its pretty important that the static name of the carrier class 
not appear in generated bytecode.  As a result, we will have to use a 
reference type (object or interface), which means we get the null 
channel "for free".