Should Rust channels panic on send if nobody's listening?

Lately, I've been working on several real-world systems using Rust's async and tokio. As you can see on the areweasyncyet.rs site, this requires using nightly Rust and the experimental tokio-async-await library. I hope to talk more about these experiences soon!

But today, I want to talk about channel APIs in Rust. A question was raised by @matklad on GitHub:

I've migrated rust-analyzer to crossbeam-channel 0.3, and the thing I've noticed is that every .send is followed by .unwrap. Perhaps we should make this unwrapping behavior the default, and introduce a separate checked_send which returns a Result?

BurntSushi followed up on Reddit:

Because the vast majority of uses of send are like this: ch.send(foo).unwrap(). That is, you panic because you generally regard it as a bug if you're still sending values when all receivers have been dropped. Why? Because this is generally a property of the program's organization.

I hesitate to disagree with two such excellent developers, but my experiences with this issue are almost the exact opposite of matklad's and BurntSushi's.

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