Tagged union typechecking regression

[robarnold]

Checkout 612f447e698ad127f57af1900e82923b8f5fee9b in my fork and try to build. I see the following error:
../src/lib/aio.rs:50:8:50:17: error: mismatched types: expected port[iorequest] but found port[iorequest](types differ)

This used to work a few days ago but I've lost track of which working version I was on.

[brson]

It is rightly a type mismatch, but the second type reported is incorrect (issue #516). In fn iotask, a port[ctx] is attempting to receive an iorequest (where ctx is defined as chan[iorequest]). So either the port type needs to be port[iorequest] or the received type needs to be ctx.

[brson]

After further looking at the port type checking, there may yet be an issue here. Investigating.

[brson]

After further investigation, I believe the typechecking for ports is ok and the example has a type error as explained above.

[robarnold]

I have no idea how this used to typecheck or how that error got introduced. Awesome!