The author is showing the result of s==nil and i==nil, which are checks that you would have to do almost everywhere (the so called "billion dollar mistake")
It's not about Printf. It's about how these two different kind of nil values sometimes compare equal to nil, sometimes compare equal to each other, and sometimes not
Yes there is a real internal difference between the two that you can print. But that is the point the author is making.
> It's a contrived example which I have never really experienced in my own code (and at this point, I've written a lot of it) or any of my team's code.
It's confusing enough that it has an FAQ entry and that people tried to get it changed for Go 2. Evidently people are running in to this. (I for sure did)
That's really my problem with these kind of critiques.
EVERY language has certain pitfalls like this. Back when I wrote PHP for 20+ years I had a Google doc full of every stupid PHP pitfall I came across.
And they were always almost a combination of something silly in the language, and horrible design by the developer, or trying to take a shortcut and losing the plot.
I believe you that you've never hit it, it's definitely not an everyday problem. But they didn't make it up, it does bite people from time to time.
It's sort of a known sharp edge that people occasionally cut themselves on. No language is perfect, but when people run into them they rightfully complain about it
It's a contrived example which I have never really experienced in my own code (and at this point, I've written a lot of it) or any of my team's code.
Go had some poor design features, many of which have now been fixed, some of which can't be fixed. It's fine to warn people about those. But inventing intentionally confusing examples and then complaining about them is pretty close to strawmanning.