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Comment by varjag | Hacker News Reader

The dangling parens make me super skeptical about quality of the advice.

I would appreciate a little bit more detail here so that the article can be corrected. Could you point to which dangling parens need to be fixed?

  (defun main
    ()
    (format t "Hello world")
  )

Should be

  (defun main ()
    (format t "Hello world"))

The lisp community has very well established formatting conventions. You pretty much never see closing parens on their own line like this except when reading code written by beginners (or some special cases like package export lists for example, where one might want to leave the list "open" for adding new symbols, similar to a trailing comma in some other languages).

> The lisp community has very well established formatting conventions. You pretty much never see closing parens on their own line like this except when reading code written by beginners

Why is that? Space efficiency? As an outsider, I find the "wrong" example more readable.

Once you use Lisp a bit, the parentheses fade away.

It's like bicycle riding. As a beginner one thinks those supports wheels at the sides of the bicycle are absolutely necessary. One is constantly struggling to keep upright. Once you can ride a bike without them, one asks if they were ever necessary. Then one never thinks consciously about keeping balance.

As said in the sibling comment, it mostly fades away and you see the structure with indentation - very much how you would in Python.

Dangling parens are the loose closing parens on separate lines. I.e. this:

  (defun plus (x y)
    (+ x y)
  )

instead of this:

  (defun plus (x y)
    (+ x y))

It suggests the author tires to balance parens manually/visually rather than using a proper editor mode. An understandable and common mistake of a newbie, but looks bad when you are writing a tutorial.

Thanks, noted. Fixed now!

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