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> )))))

You could stack them like this in every language but only in Lisp do people actually do it. Lisps bad habbit of stacking all the parentheses like that is what makes it so hard to read. It is easier to write that way, but it is very hard to understand how many contexts up you just moved.



> Lisps bad habbit of stacking all the parentheses like that is what makes it so hard to read.

How much Lisp have you written/read? Closing parens on separate lines would be a nightmare to read in any real-world code.

Also, what makes Lisp hard to read is lack of familiarity. It's not like C is easy to read for someone who's only ever written Lisp. Lispers don't find Lisp hard to read.


Sounds like a good opportunity to oil up Chesterton’s fence. You may want to consider the possibility that the conventions Lispers have been using for considerably longer than C or whatever language you like to bikeshed style guides in has existed were actually settled on for pragmatic reasons.

You’re not alone though. Many nascent Lispers go through the use reader macros to make Lisp look more like what they’re used to phase.


Not just nascent Lispers. I inherited something like this in a C codebase before (several times, actually, only one that I had to actually edit though):

  #define BEGIN {
  #define END }
  #define INTEGER int
  ...
Yes, they even did it with the types. Made for a weird Pasctran language that the dev was apparently more comfortable with. I think they actually got a C translation of another program almost "for free" doing this. The real thing was they didn't want to write new code and didn't want to learn C, so they subjected everyone after them to this horror.

Moral of the story: If you can't be bothered to learn a language and its conventions, be honest and get another job.


Pasctran is an ancient cult. [1] Some say they're extinct. Others say its practitioners have just gone underground, now that society will no longer tolerate such things done in public. It's everywhere once you start looking though, insidiously contaminating our precious function bodies.

From the source to the original Bourne shell:

    BEGIN
       REG BOOL slash; slash=0;
       WHILE !fngchar(*cs)
       DO    IF *cs++==0
        THEN    IF rflg ANDF slash THEN break; ELSE return(0) FI
        ELIF *cs=='/'
        THEN    slash++;
        FI
       OD
    END
[1] https://research.swtch.com/shmacro


As an old Pascal programmer who never really liked C.... even I have to say NO!!!!

What a horrible thing to do. I've never liked macros, and things like this are part of the reason why.


Not with proper indenting, or rainbow-delimiters/show-paren-mode.


I don't buy that, when you do the same in other languages you get:

    for (var i = 1; i < 101; i++) {
        if (i % 15 == 0) {
          console.log("FizzBuzz");}
        else if (i % 3 == 0) {
          console.log("Fizz");}
        else if (i % 5 == 0) {
          console.log("Buzz");}
        else {
          console.log(i);}}

Why do you think nobody other than lispers writes code like this? Is it really necessary to write code that way? If it is better, why not does nobody else do it? They can also use colored bracers and tooling, while lispers has written code that way forever.

I'm sure a big reason people call lisp a "write only language" is because of this strange convention of stacking all parentheses in a big clump instead of formatting like normal.


Yet, for Python the layout is like above, with indentation being significant:

  for i in range(1, 101):
      if i % 15 == 0:
          print("FizzBuzz")
      elif i % 3 == 0:
          print("Fizz")
      elif i % 5 == 0:
          print("Buzz")
      else:
          print(i)
 
It does not need the {} pairs then. Now, are we lost because the {} pairs are missing?

In Lisp you need to learn to apply the same idea of indentation being significant:

  (loop for i from 1 upto 100 do
     (cond ((zerop (mod i 15))
            (write-line "FizzBuzz"))
           ((zerop (mod i 3))
            (write-line "Fizz"))      
           ((zerop (mod i 5))
            (write-line "Buzz"))
           (t
            (write-line (princ-to-string  i)))))
Just imagine the grouping parentheses are not there.

The disadvantages of Lisps are basically two:

a) there are more parentheses because of the nested lists being used to write code

b) one now needs to understand when (sin a) is actually code and when it is data.

The advantage of Lisp syntax:

a) code is already a simple nested data structure

b) the indentation&layout of code can be (and often is) computed from the data, while usually in Python the lines and indentation are significant


Do you want Python? Because this is how you get Python.

Joke aside, this is why I never understood this problem. With proper indentation it looks essentially like Python with a generous helping of your-father's-parentheses.


>when you do the same in other languages you get...

Your result should be unsurprising. Lisps have a minimal syntax that naturally entails high levels of nesting: (s-)expressions being used to represent functions, control structures, data, etc.

Why should a particular style convention appropriate for that kind of language necessarily transplant well to JavaScript-- a brace-delimited, Algol-inspired language with a lot of syntax?


I used to feel the same way but lisp gets easier to read with practice, and unless you're writing code in notepad.exe or nano or something, your editor will show you the matching paren.


IMO, because C syntax sucks and makes people actually take time to read and interpret the brackets. In erlang and I think others people don't newline between closing delimiters either. In lisp the brain processes the parens automatically.


Who calls Lisp a "write only language" other than people who don't know Lisp?


There is the classic Minsky quote:

“Anyone could learn Lisp in one day, except that if they already knew Fortran, it would take three days.”


Is it bad that I find that really easy to read?


But why would you care about those trailing parentheses?


Readability. By properly indenting the parentheses and putting them on lines you will at a glance see which contexts you just closed, that is how people format code in every mainstream language.


None of these 'mainstream' languages use a data structure for writing and manipulating code like Lisp. The use of Lisp is thus very different and Lisp programmers find a more compact notation more useful.

> you will at a glance see which contexts you just closed

the text editor does that for me

> how people format code in every mainstream language

Python code formatting looks different from Java code formatting.

Python code:

  for h in range(0, height):
      for w in range(0, width):
          v = bw_image.getpixel((w, h))
  
          if v >= avg:
              bm_image.putpixel((w, h), white)
          else:
              bm_image.putpixel((w, h), black)
Lisp code just looks like that. Only with added parentheses (because Lisp expressions are written as nested lists) and prefix notation:

  (dotimes (h height)
    (dotimes (w width)
      (setf v (get-pixel bw-image w h))

      (if (>= v avg)
          (put-pixel bm-image w h while)
          (put-pixel bm-image w h black))))


Python also formats their parentheses the non lisp way. You typically format things like this:

  data = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9, [10, 11, 12]]
  ]
Any language that uses closing symbols formats them that way, in Pyhton in Java, in C etc. Lisp is the only example where they don't properly indent closing symbols and instead just put them all together at the last statement.


Yet most Python code is written in the compact form I've showed you, where code indentation is significant. Lisp has the same model: the code indentation is significant. But Lisp has the structure encoded in nested lists. These nested lists are automatically formatted in the same space saving way as Python code. Due to the significant indentation, Python usually can avoid to have grouping characters/symbols.

I see also lots of Python code where data isn't written like you claim...

https://www.programiz.com/python-programming/matrix


With lisp is it not more common to use paredit or similar? I.e. you don’t edit code like in other languages.

As you barf and slurp, you’re interested in the “shape” of code but you ignore the parens.


> but only in Lisp do people actually do it

That is false. Do yourself a favor and run "git grep -F ')))))' in, oh, the root of the Linux kernel tree.


There is a real drawback to stacking more than three or four closing parens like this, without spacing them out: it's hard and in fact impossible to count them at a glance. Not an issue if you have a code editor with auto paren matching, but it can be an annoyance when reading LISP-like code on the web or elsewhere.


> it can be an annoyance when reading LISP-like code

Just mentally collapse any number of consecutive close parens into a thing that reads like "END."


In Interlisp one would write a super parenthesis, which closes all open parentheses, upto an opening [ or the top ( :

  (a (b c (d ]
and also

  (z (a [b c (d]
        [e f (g]]


Nah, you just rely on the indentation to understand the structure, just like every other language.


It's not a bad habit. It's just more practical.

Lisp lists are a data structure. One for example types code&data and computes with an interactive Read Eval Print Loop.

That's what one would write:

  CL-USER 35 > (+ (expt 23 2.4) (sin (* 44 0.23 22)))
  1854.5603
No one would type:

  CL-USER 36 > (+ (expt 23 2.4) (sin (* 44 0.23 22
                                     )
                                )
               )
Also when Lisp deals with s-expressions, the more compact notation is more useful: here Lisp does the layout itself:

  CL-USER 46 > (let ((*PRINT-RIGHT-MARGIN* 30))
                 (pprint '(+ (EXPT 23 2.4) (SIN (* 44 0.23 22)) (COS (+ 12 0.43 19.0)) (TAN (/ 1.4 0.77 3/4)))))

  (+ (EXPT 23 2.4)
     (SIN (* 44 0.23 22))
     (COS (+ 12 0.43 19.0))
     (TAN (/ 1.4 0.77 3/4)))
It's not

  (+ (EXPT 23 2.4
     )
     (SIN (* 44 0.23 22
          )
     )
     (COS (+ 12 0.43 19.0
          )
     )
     (TAN (/ 1.4 0.77 3/4
          )
     )
  )
Above is much harder to read and wastes a huge amount of space on the screen. Imagine that lists of are much longer and deeper nested. Finding the corresponding parentheses is usually done by using the editor (select a whole expression, have blinking or colored parentheses, etc.).

The main difference between Lisp and most other programming languages is that programs are written as a data structure: nested lists. Not only that: they are not static lists, but we can compute with them - that's the main appeal. It's a programming language, where it's easy and common to manipulate lists, even programs as lists. Thus the notation has not only be useful for reading code, but also for input/output by humans and programs. There a compact notation is much more useful, since tools will often create huge amounts of nested lists. For example imagine a macro for some Lisp functionality, like a complex loop expression. The macro expanded code can often be ten times larger as the input expression, yet we may want to see it in a debugger -> write that expression in a compact way.

I let Lisp indent my code and the system-wide standard indentation makes it easier to spot parentheses errors, since all code has the same shape rules.

  (progn
    (case foo
      (var (eval foo)))
    (fn (apply foo args)))
Since all code gets indented during typing, I can easily see that there is one parenthesis too much in the first case clause...

I wouldn't care to see the parentheses aligned and it makes the problem often more difficult to spot:

  (progn
    (case foo
      (var (eval foo
           )
      )
    )
    (fn (apply foo args
        )
    )
  )
I want the expressions to use less vertical space, so that I can see that the opening parentheses of the CASE clauses align. Anything else is just visual clutter.


The standard way is to close inline things inline and close multi-line things on a separate line.

Like this:

  (+ (EXPT 23 2.4)
     (SIN (* 44 0.23 22))
     (COS (+ 12 0.43 19.0))
     (TAN (/ 1.4 0.77 3/4))
  )
Instead of

  (+ (EXPT 23 2.4)
     (SIN (* 44 0.23 22))
     (COS (+ 12 0.43 19.0))
     (TAN (/ 1.4 0.77 3/4)))


It is very common for programmers who are new to Lisp to close their parentheses in the former style. However, it is a crutch that they soon do away with if they stick to the language for any length of time.


There are two reasons why sometimes the parentheses are on a separate line:

  ((paris (french))
   (los-angeles (english spanish))
   )
Something like above would be used if one often adds data clauses to that expression.

Also when there are comments on the last line, then sometimes the expression might be closed on the following like:

  ((paris (french))                 ; city 1
   (los-angeles (english spanish))  ; city 2
   )


Actually that's also wrong, I usually see this rule applied in other languages:

If the opening bracket is on the same line as content, then so is the closing bracket.

By this rule, we have two options:

  (+
     (EXPT 23 2.4)
     (SIN (\* 44 0.23 22))
     (COS (+ 12 0.43 19.0))
     (TAN (/ 1.4 0.77 3/4))
  )
or

  (+ (EXPT 23 2.4)
     (SIN (\* 44 0.23 22))
     (COS (+ 12 0.43 19.0))
     (TAN (/ 1.4 0.77 3/4)))

The first option has both opening and closing brackets on their own lines, while the second has neither. Note that I consider the function name to be part of the opening bracket since it's distinct from the parameters.

This is consistent with other languages:

  [1, 2, 3]
  f(x, y, z)
  [
    1,
    2,
    3,
  ]
  f(
    x,
    y,
    z
  )
instead of

  [1,
   2,
   3,
  ]
  f(x,
    y,
    z,
   )


Haskell is an odd exception with

    [ x
    , y
    , z
    ]
which looked really weird to me first but I’ve found it to improve legibility a lot. (Of course there’s a reason it’s idiomatic in Haskell and not elsewhere.)


Lisp has lots of multi-line expressions.

That the expression is ended I can see in the typical Lisp expression because of the block structure. The single parentheses does make the layout very cluttered and visually ugly. It gets even worse in typically larger Lisp code or data.




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