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Comment by VyseofArcadia | Hacker News Reader

That said, it would be nice if lisp used square brackets for this instead. Easier to type on boring old US QWERTY.

No problem, just a couple reader macros! (Adapted from an answer on https://stackoverflow.com/questions/1988/how-far-can-lisp-ma...)

  ;; Make [] == ()
  (set-syntax-from-char #\[ #\( )
  (defun lbrace-reader (stream inchar)
  (declare (ignore inchar))
  (read-delimited-list #\] stream t))
  (set-macro-character #\[ #'lbrace-reader)
  (set-macro-character #\] (get-macro-character #\) ))
  (set-syntax-from-char #\] #\) )

Parentheses are so much more frequently typed than square brackets in almost every context that you are better off following the Lisp Machine keyboard layout and swapping them on your keyboard even if you do not program in Lisp:

https://news.ycombinator.com/item?id=14985932

Yes, agreed. From your previous comment:

> Apple does not provide a way to do these remappings on OS X

Run Emacs (or XEmacs) under XQuartz and you can do whatever remapping you want. This is how I deal with it.

Another choice is a fully programmable keyboard, though these also tend to have nonstandard layouts that require some retraining.

There is no need for X, you can just use elisp, i.e.: (keyboard-translate ?\[ ?\()

And unless you do need X, I suggest using Emacs-Mac-Port instead of of the official Emacs: https://bitbucket.org/mituharu/emacs-mac/overview

Some lisps use parenthesis and brackets interchangeably. Some people prefer to strategically alternate them, but you're free to use them exclusively.

Guile Scheme, for example:

  scheme@(guile-user)> [list 1 2 3] 
  $1 = (1 2 3)
  scheme@(guile-user)> (list 1 2 3) 
  $2 = (1 2 3)
  scheme@(guile-user)> [car '[1 2 3]]
  $3 = 1

While true, this is not officially supported as part of the RnRS standard I believe. They set these characters aside as reserved for future use.

Yes, you're correct. R7RS at least explicitly reserves brackets and braces, and only acknowledges parenthesis in its syntax.

I think this depends on which RnRS you look at.

Do some of the older ones just completely omit reserving them?

R6RS: pairs and lists, enclosed by ( ) or [ ] (see section 4.3.2)

Ah the problem child. :) I've mostly only paid attention to R5RS and R7RS.

I'd like to see square brackets replace the backtick.

I only have a cursory familiarity with lisps but I constantly find that too easy to miss.

Racket can use either. They are syntactically equivalent, but there are some community norms around when to use each. Racket’s included editor DrRacket takes the [ and ] keys and figures out which to use using those conventions, inserting either [ or ( as appropriate

Square brackets are AltGr-8 and AltGr-9 on German T2, but Parens are Shift-8 and Shift-9, which is much nicer on the hands.

So I’m going to be against this.

Rebol and Red are very Lisp like and use square brackets instead of paren's.

    $ setxkbmap -option parens:swap_brackets

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