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Comment by ecto | Hacker News Reader

loon is a lisp! https://github.com/ecto/loon

  [type Shape
    [Circle Float]
    [Rect Float Float]]
  
  [fn area [s]
    [match s
      [Circle r]  => [* 3.14 r r]
      [Rect w h]  => [* w h]]]
  
  [area [Circle 5.0]]

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idk how I haven't crossed a lisp with square brackets but dang I am sorta stunned at how I've never even envisioned it? thanks

No shift key needed for square brackets!

Curl was a proprietary Lisp that {curly brackets} and was designed in the 1990s to build web applications.

https://en.wikipedia.org/wiki/Curl_(programming_language)

I've always found OCaml's (* ... *) comments annoying, because it needs shift for both characters. But I suspect it's easier to type on a french keyboard.

Knuth solves the bracket issue by redefining his keymap to swap () with [] and + with = (macos keymap files found at the bottom of this page: https://www-cs-faculty.stanford.edu/~knuth/programs.html )

In high school I tried spec'ing a lang that excluded shift key usage... fun times.

Keyboards of early MIT systems[1] and Lisp Machines[2] had brackets (parentheses) and square brackets on the same key where square brackets and curly brackets are on modern keyboards.

1: http://xahlee.info/kbd/sail_keyboard.html

2: http://xahlee.info/kbd/space-cadet_keyboard.html

There's a few lispy languages that support using square brackets as an alternative to parens. Racket even has curly braces too.

The above really reminds me of tcl, though, which uses square brackets to force evaluation of the command they wrap.

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