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Comment by gorgoiler | Hacker News Reader

Lexical Scanning In Go is a charming piece of programming:

https://m.youtube.com/watch?v=HxaD_trXwRE

A good debuggable piece of code explains what it is trying to do by being clearly written and conforming to a consistent and logical model. I don’t think I would ever have invented this type of lexer pattern in Go by myself, but would be very grateful to come across it in a code base I had to fix. Like Duff’s Device mentioned in this thread, it has just the right amount of cleverness without becoming inscrutable.

Also, if you’ll excuse some avuncular pride, my niece and I wrote some code yesterday. She asked me how many times grandma’s clock chimes every day and we ended up with the following Ruby:

  2 * (1..12).reduce(&:+)

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Cool one liner! Here's some other languages:

Python: 2 * sum([x for x in range(1, 13)])

Haskell: 2 * sum [1..12]

You don't need the list comprehension for python - just 2 * sum(range(1, 13))

And drop the 1, too

I prefer the explicit example for being explicit, I find it more pythonic.

GPs example is perfect Python; every character has meaning, and it's extremely readable even for non-programmers.

What’s quite elegant about Ruby (in and of itself, not in comparison to your examples) is how consistently it is implemented using its own simple set of core features, with very little magic or syntactic sugar. reduce, Enumerable, what the & operator is doing etc.

What’s so challenging about Ruby is how the language can be abused by library vendors to make all kinds of surprising magic and homegrown syntactic sugar.

> What’s quite elegant about Ruby is how consistently it is implemented using its own simple set of core features, with very little magic or syntactic sugar.

Honestly, I don't think this has much to do with Ruby. This a consequence of using reduce or any other higher-order functions, which come from functional programming, and are now available in almost all modern multi-paradigm programming languages (including Python and Haskell).

I you like this kind of constructs, you should definitely learn a functional programming language, you'll love it.

  2 * (1..12).reduce(&:+)

You could also use the closed summation formula: (n^2 + n) / 2. In our case that shortens to just 12*13=156.

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