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that an who the fuck uses interface literals? I do Go personally and professionally for years and never seen it.

The Go standard library uses it. I didn't suss out the reason for it though.

An example is in the errors package: https://cs.opensource.google/go/go/+/refs/tags/go1.23.0:src/...

I was about to say, after so many years doing Go, I have never seen this and would love to read blog post about why interface literal is useful.

You can learn from the Go codebase to get a feel of why this is useful:

https://github.com/golang/go/blob/master/src/cmd/go/internal... https://github.com/golang/go/blob/master/src/io/fs/fs.go#L26... https://github.com/golang/go/blob/master/src/errors/wrap.go#... https://github.com/golang/go/blob/master/src/go/parser/resol...

If the interface check fails, does the code panic or does the `ok' value just get set to false?

If `ok' gets set to false, that seems optimal. Pretty neat, in fact, what other language permits such low-key, easy runtime interface checks?

this will panic:

v := hello.(world)

this never panic:

v, ok := hello.(world)

and yes, its awesome. people rag on Go because BLARG ERRORS BOILERPLATE, but if you can get over that Go is not Python/JavaScript, you're left with a simple powerful language

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