I really wished json5 would support optional commas as well. If you have a new line, no comma needed. So you can do

[

1

2

3

]

New lines used by humans, computers should do a good job as well.

It looks very like an s-expression. Maybe we should go back to Lisp for our data encoding? (and to our code when we are at it? ;))

Like https://hjson.org/?

Well you could use CSON, which uses CoffeeScript notation that allows for constructs such as:

required: [

  'firstName'

  'lastName'

]

which is the same as:

{

  "required": [

    "firstName",

    "lastName"

  ]

}

in JSON :)

That's not a subset of JavaScript though.