[ecto]

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]]

[grimgrin]

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

[cpeterso]

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)

[syene]

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

[shawn_w]

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.