tbf positional arguments are already bad enough. Now if you’re using over 9 positional args… just take a break, go for a short walk, and maybe you’ll come back with a better plan
I do think the unnumbered variant of such anonymous parameters is useful, if you’ve got a team of devs that knows not to misuse them.
In particular, folks who are unexperienced will gladly make massive multi-line transformations, all in one step, and then continue blathering on about it or similar, as if everyone knew what they were talking about and there was no potential for ambiguity.
This is also particularly annoying, because you rarely read code top-to-bottom. Ideally, you should be able to jump into the middle of any code and start reading, without having to figure out what the regional abbreviations or it mean.
That deserves an “always has been” meme… But IMO, Ruby outperled Perl since the beginning.
Perl doesn’t let you redefine the syntax so that you can write the same program multiple ways. All it does is to encourage multiple programs to have the same meaning.
It wouldn’t be as relevant, since passing a function or method instead of a closure is much easier in Rust - you can just name it, while Ruby requires you to use the method method.
So instead of .map(|res| res.unwrap()) you can do .map(Result::unwrap) and it’ll Just Work™.
In the case of your example we’d do .map(&:unwrap) in Ruby (if unwrap was a method we’d actually want to call)
Notably, these are not the cases _1 and _2 etc are for. They are there for the cases that are not structurally “call this method on the single argument to the block” e.g. .map{ _1 + _2 } or .map { x.foo(_1) }
(_1 is reasonable, because iterating over an enumerable sequence makes it obvious what it is; _1 and _2 combined is often reasonable, because e.g. if we iterate over a key, value enumerable, such as what you get from enumerating a Hash, it’s obvious what you get; if you find yourself using _3 or above, you’re turning to the dark side and should rethink your entire life)
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