Languages like Go, is how you end up with what appears simple on the surface, while in reality is full of gotchas and boilerplate for what complex languages support out of the box.
replyThat is how you get double nils, exception handling that pretends not to be one, url based imports that requires source code and rewrites when the host changes, generators by code patterns, generics that miss some language constructs,....
None of those are real problems in reality, I don't think Go has more gotchas than other languages.
replyWritten a few hundred kloc of go and I'd never heard of double nil. Turns out it's nasty.
reply var i interface{} // (Type: nil, Value: nil) -> i == nil is TRUE
var p *int = nil // p is nil
i = p // (Type: *int, Value: nil) -> i == nil is FALSE!While this behavior can be counterintuitive, it's easy to understand once you have the right mental model of interface values. A nil interface is an empty interface. Once p is assigned to i, then i is no longer empty: it holds a nil pointer to an int. Whether the interface is empty or not is one question, answered by comparing it against nil. Whether the value the interface holds is a nil value is another question, answered by downcasting and then checking the resulting value.
replyI don't blame people for being confused by this the first time they encounter it. However, anyone who finds it persistently challenging to understand is not going to have much luck with the subtler language features of C++, Rust, Typescript, etc.
> url based imports that requires source code and rewrites when the host changes
replyThis is not the case. It can be avoided quite easily with 'replace' directives and/or GOPROXY.
Yes, I meant that with my mention of rewrites, and it is design wart that such workarounds are required in first place.
replyThis is just how I've felt writing both Rust and C++. Rust's language complexity often feels like it's there so that I don't have to think about so much complexity when interfacing with the code, whereas C++'s language complexity introduces footgun after footgun and I have to think very carefully about what everything could possibly do (e.g. if destructors even get run in certain instances when I'd expect them to).
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