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eamonnsullivan
Clojure 1.6, Emacs 24.5... These are pretty old versions, at least of those.
waffletower
I have been a clojurist for more than a decade and I started with Clojure 1.7. 1.6 was released in 2014!
arikrahman
Would be interesting to see how Jank is coming along in this space as well.
sinsudo
I know that the purpose of the page is to compare syntax of common lisp, racket, clojure, and emacs lisp. But some examples could be more idiomatic, for instance instead of

  (defun add (a &rest b)
    (if (null b)
        a
        (+ a (eval (cons '+ b)))))
One should avoid eval and use endp instead of null:

   (defun add (a &rest b)
        (if (endp b) a
            (apply #'add (+ a (first b)) (rest b))))
ethagnawl
This is really neat.

Something I've been meaning to do is try putting together a cross-lisp package manager -- if only because it'd be fun. Maybe it would favor code that could be readily run or eval'd or maybe with some sort of clj/cljs type dynamic dispatch for anything implementation specific.

sinsudo
The page indicates that there is not function for documentation in common lisp, but

  (documentation 'documentation 'function)
      "Return the documentation string of Doc-Type for X, or NIL if none 
        exists. 
        System doc-types are VARIABLE, FUNCTION, STRUCTURE, TYPE, SETF, and T.

 Also http://rosettacode.org for computer tasks implemented in many computer languages to allow you compare syntax and code.
FrustratedMonky
Nice comparison.

But makes me think we'd be better off if we all just focused on a single one, and grew it, made it better. Not having 4 versions of something almost identical. Fragmentation can hurt adoption.

FergusArgyll
As someone who's not a programmer but has beginner - medium python & C skills. I'm in middle of learning lisp (elisp to be precise) and it feels like reading poetry. It's a transcendent experience that's hard to explain. Such beautiful concepts. Everything flows in a way it doesn't in C based langs
vindarel
Notes on CL:

- why nothing on the "compiler" line? Everytime you load a snippet or a file with SBCL, it compiles it (to machine code). There's also compile-file.

- interpreter: likewise, all code is compiled by default with SBCL, not interpreted, even in the REPL. To use the interpreter, we must do this: https://github.com/lisp-tips/lisp-tips/issues/52

- command line program: the racket cell shows the use of -e (eval), the same can be done with any CL implementation.

- since the string split line introduces cl-ppcre, one could mention cl-str :D (plug) (much terser join, trim, concat etc)

- ah ok, for dates and times, flattening a list, hash-table literals… we need more libraries.

- more files operations: https://lispcookbook.github.io/cl-cookbook/files.html

- emacs buffers: now compare with Lem buffers 8-)

- posix-getenv: I'd rather use uiop:getenv (comes in implementations).

- uiop:*command-line-arguments*

- exit: uiop:quit

- uiop:run-program (sync) / launch-program (async)

- java interop: with LispWorks or ABCL (or other libraries)

my 2c

tmtvl
Hash-table literals are covered by (among others):

  - Serapeum
  - golden-utils
  - rutils
  - make-hash
Though now I'm wondering which libraries would make for a proper canonical extended core... asdf, uiop (comes with asdf, so naturally), alexandria, bordeaux-threads, cffi, cl-ppcre, str, local-time, trivia,... and maybe fset? (although I personally prefer Sycamore's naming conventions)

...maybe also fivem (although I personally prefer parachute) and hunchentoot.

aidenn0
CL list comprehension:

  (loop for file across "ABCDEFGH"
        nconc (loop for rank from 1 to 9
                    collect (format nil "~C~D" file rank)))
Jach
Or with more Python-esque syntax:

    (let ((files (coerce "ABCDEFGH" 'list))
          (ranks (loop for r from 1 to 9 collect r)))
      [(format nil "~a~a" file rank) (file <- files) (rank <- ranks)])
Based on the list comprehension macro from 1991 in https://3e8.org/pub/scheme/doc/lisp-pointers/v4i2/p16-lapalm... that still works.

    (defmacro comp ((e &rest qs) l2)
      (if (null qs) `(cons ,e ,l2) ; rule A
          (let ((q1 (car qs))
                (q (cdr qs)))
            (if (not (eq (cadr q1) '<-)) ; a generator?
                `(if ,q1 (comp (,e ,@q) ,l2) ,l2) ; rule B
                (let ((v (car q1)) ; rule C
                      (l1 (third q1))
                      (h (gentemp "H-"))
                      (us (gentemp "US-"))
                      (us1 (gentemp "US1-")))
                  `(labels ((,h (,us) ; corresponds to a letrec
                              (if (null ,us) ,l2
                                  (let ((,v (car ,us))
                                        (,us1 (cdr ,us)))
                                    (comp (,e ,@q) (,h ,us1))))))
                     (,h ,l1)))))))

    (defun open-bracket (stream ch)
      (do ((l nil)
           (c (read stream t nil t)(read stream t nil t)))
          ((eq c '|]|) `(comp ,(reverse l) ()))
      (push c l)))

    (defun closing-bracket (stream ch) '|]|)

    (set-macro-character #\[ #'open-bracket)
    (set-macro-character #\] #'closing-bracket)
Supports filtering too, e.g.

    (let ((xs '(1 2 3 4))
          (ys '(1 2 3 4)))
      [(+ x y) (x <- xs) (y <- ys) (evenp x) (oddp y)])
    ; -> (3 5 5 7)
aidenn0
I didn't try macroexpanding it yet, but when I make the 9 a runtime-parameter, I eventually get a stack-overflow with SBCL not TCO-ing the "H" binding in labels.

The comments make me think this is ported from scheme, which has precise TCO rules.

[edit] macroexpanded:

    (LABELS ((H-37 (US-38)
               (IF (NULL US-38)
                   NIL
                   (LET ((FILE (CAR US-38)) (US1-39 (CDR US-38)))
                     (LABELS ((H-43 (US-44)
                                (IF (NULL US-44)
                                    (H-37 US1-39)
                                    (LET ((RANK (CAR US-44)) (US1-45 (CDR US-44)))
                                      (CONS (FORMAT NIL "~a~a" FILE RANK) (H-43 US1-45))))))
                       (H-43 RANKS))))))
      (H-37 FILES))
dfox
> cannot start with digit

Not only it can, but both CL and Emacs Lisp actually defines primitives with names that start with digit.