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Comment by rtpg | Hacker News Reader

this is more of a "symbols per line" argument rather than "symbols in the language" argument.

    grade = (student) ->
      if student.excellentWork
        "A+"
      else if student.okayStuff
        if student.triedHard then "B" else "B-"
      else
        "C"

(from coffescript examples)

Imagine how many more symbols that would have in any lisp dialect

View on HN

    (defun grade (student)
      (cond ((excellent-work student) :a+)
            ((okay-stuff     student) (if (tried-hard student) :b :b-))
            (t                        :c)))

Erlang, just for fun:

  grade(#student{work=Work, tried_hard=Tried}) -> grade1(Work, Tried).
  grade1(excellent_work, _) -> 'a+';
  grade1(okay_stuff, yes) -> b;
  grade1(okay_stuff, _) -> 'b-';
  grade1(_, _) -> c.

Edit: formatting.

Or, if we're going to go with Prolog-inspired syntax, then why not Prolog?

    grade(Student, Grade) :-
        worked(Student, Work), work_grade(Work, Student, Grade).
    work_grade('Excellent', _, 'A+').
    work_grade('Okay', Student, 'B') :- tried_hard(Student).
    work_grade('Okay', _, 'B-').
    work_grade(_, _, 'C').

I'm a bit rusty, and I don't have a Prolog interpreter to hand to test, so I might have got some syntax wrong.

I'm always amazed that I hardly ever program in Lisp and yet these short snippets are more readable than any other language.

Yes, I've never understood why

    dostuff(x)

is considered so much more readable than

    (dostuff x)

   ;; comparing with racket:

   (define (grade student)
     (cond 
      [(excellent-work student) "A+"]
      [(and (okay-stuff student) (tried-hard student)) "B"]
      [(okay-stuff student) "B-"]
      [else "C"]))

   ;; Or

   (require racket/match)

   (define (grade student)
     (match (map (lambda (fn) (fn student)) 
                 '(excellent-work okay-stuff tried-hard))
       [(list #t _ _)  "A+"]
       [(list _ #t #t) "B"]
       [(list _ #t _)  "B-"]
       [else           "C"]))

Clojure:

    (defn grade [student]
      (cond
        (excellent-work student)  "A+"
        (okay-stuff student)      (if (tried-hard student) "B" "B-")
        :else                     "C"))

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