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Comment by a_c | Hacker News Reader

OT, we used to joke about LISP source code contains mostly brackets. Nowadays we literally store, transform and pass around willy nillily

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Speaking about LISP and state in the URL, this is how OVH stores the state when you buy a domain from them:

    https://www.ovh.com/fr/order/webcloud/?#/webCloud/domain/options?selection=~(domains~(list~(~(name~'somethinghn.com))~options~(~'dnssec)))

That's Clojure's EDN encoded for ClojureScript isn't it? I recognize this syntax from briefly working on a CLJ/CLJS app.

Nope, edn uses square brackets and doesn't have a `list` keyword. This is some custom representation.

Probably written in Common Lisp? Based on some quick searching I found this reference https://docs.ovh.com/us/en/web-paas/languages-lisp/

Or it could just be that s expressions are easy to parse.

we used to joke about LISP source code contains mostly brackets.

There was a programming language in the 1970's called SAM76 that didn't care how many closing parentheses you had, as long as it was more than the number of opening parentheses.

So, something like this was perfectly valid:

  a(1+r(em(2)))))))))))))))))))

That's genious IMO. Making sure the amount of opening and closing parantheses is equal is annoying and unnecesary.

It screams "trust me all good with the closing parantheses".

paredit and rainbow parens makes it a non-issue for me.

I disagree. I would say when I get an unbalanced paren compiler error, it's more common for the omission to not be at the end of the line. Having the compiler silently swallow the error would lead to serious bugs very quickly.

What if I wanted to copy that expression and use is as part of a different expression?

Interactive prompts already do that. Eg if you google "2+2)*3" it will correctly print "12". This effectively lets you append operations to an expression without editing both sides.

On the other hand, auto closing parentheses in code is a terrible idea for obvious reasons. There are only like 7 languages used in industry and they all have excellent tooling that integrates with your editor to eliminate issues like this.

    if ((v1.x()-v2.x())*(v1.x()-v2.x())+(v1.y()-v2.y())*(v1.y())-v2.y())+(v1.z()-v2.z())*(v1.z()-v2.z()) > distance*distance) {
        // collision
    }

Would you like this to fail to compile? Or would you prefer it to silently return the wrong value?

I'd prefer the compiler file an HR complaint against the author.

if collisioncheck(v1,v2, distance) { // collision }

where you have defined an actually readable equivalent inside of collisioncheck would be my prerogative... I also agree paren matching failures should error, but your example is NOT why.

Relevant xkcd: https://xkcd.com/859

I found that joke funny until I realized that, if you sum the count of round, square, angle and curly braces together, your typical piece of C++ or Java code has more brackets than equivalent piece of Lisp code...

Right, but having them all be the same is what people are joking about :) Although I might check the lisp/clojure vs java code on techempower or another rosetta stone like example.

That, and the usual style of stacking all closing parentheses together at the end of the last line of a sub-expression / statement / whatever. People sometimes do this in Java and it's just as unreadable.

You read it by indentation not by counting parentheses.

It's still very easy to make mistakes reading it that way. If you are reading it by indentation anyway you may as well use a parser that closes parentheses for you at indentation changes. (Like the ML family and Haskell and Python all decided to do.)

I don't find reading properly indented Lisp any harder than reading properly indented Python. I agree however with respect to having the tooling help with balancing delimiters, although I let the editor do that job instead of the parser. And that's one of the major advantages of Lisp. Structural editing is considerably easier to implement. Parinfer[1] for example is really cool. I have to say I'm really excited about tree-sitter allowing similar structural editing for harder to parse languages.

[1] https://shaunlebron.github.io/parinfer/

Well yeah that's a major reason why most programmers hate LISP syntax. It uses a parentheses for everything even though every keyboard has round, square, angle and curly braces.

I somehow doubt it. I tutored quite a few people of all ages who started to learn programming, mostly C, C++ and Java - they all initially have been mostly confused by the different kinds of brackets. They quickly understood where the brackets go (scopes/blocks, function calls, array declarations and access, etc.), but took some time to internalize which bracket type is used in which context.

I suspect the main reason programmers dislike Lisp syntax is that they try or see an example of some basic arithmetics, get surprised by the prefix notation that's so "unnatural" compared to the "obvious" infix notation they learned in primary school, and write off the entire language as weird, not noticing the fact that infix math is an exception in programming languages, as otherwise almost all code they write in any other language is in prefix notation too, just with a parenthesis shifted to the left.

A somewhat mind-blowing observation to some people:

  (foo (bar baz quux))
  
  foo(bar(baz, quux));

The two lines above are both in prefix notation. You can go from the first to the second one by a) shifting each left paren by one token to the right, and b) adding commas between whitespace-separated tokens.

I suppose beginner programmers might find all the different kinds of brackets in C++ confusing but after some experience, it helps a lot with readability. If I see `a[1]` then I know that `a` is probably an array. If I see `a(1)` then I know that `a` is probably a function. You could make the argument that those are terrible names for variables and methods and you'd be correct, but every small bit of context helps.

Like most of the verbosity in those languages it benefits the reader more than the writer.

Clojure uses [] and {}, eg. :

  (defn fib [x, n]
    (if (< (count x) n) 
      (fib (conj x (+ (last x) (nth x (- (count x) 2)))) n)
      x))

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