Okay, this is a revelation. I hadn't seen refutable lets, and this seems great!

masklinn · on Dec 22, 2014

Refutable lets also work in `while` (`while let pattern = expression { … }`), which is pretty great.

aethertap · on Dec 23, 2014

I just rewrote one of my parser functions using that, and it literally eliminated 90% of the code and improved error reporting at the same time. Very cool, thanks for the tip.

geofft · on Dec 23, 2014

Take a look at this PR: https://github.com/rust-lang/rust/pull/19405/files