jsonic

This is an implementation of a domain-specific-language based on JSON that supports embedded S-expressions.

This is part of the excellent book Beautiful Racket, which I would highly recommend checking out.

Requirements

From Beautiful Racket

• Every valid jsonic program produces valid JSON.
• Every valid JSON file is a valid jsonic program.
• Racket expres­sions can be embedded in place of any JSON value.
• Line comments start with //

Grammar

The grammar for this language, in Extended Backus–Naur form is as follows:

jsonic-program : (jsonic-char | jsonic-sexp)*
jsonic-char    : CHAR-TOK
jsonic-sexp    : SEXP-TOK

Usage

Installing the package

• This requires racket
• Clone this repository and cd into the jsonic directory
• Run raco pkg install

Testing

Once the package is installed, the following programs can be run using #lang jsonic.

#lang jsonic
[
  null,
  42,
  true,
  ["array", "of", "strings"],
  {
    "key-1": null,
    "key-2": false,
    "key-3": {"subkey": 21}
  }
]

#lang jsonic
// a line comment
[
  @$ 'null $@,
  @$ (* 6 7) $@,
  @$ (= 2 (+ 1 1)) $@,
  @$ (list "array" "of" "strings") $@,
  @$ (hash 'key-1 'null
           'key-2 (even? 3)
           'key-3 (hash 'subkey 21)) $@
]

Both of these should output the same result, but the latter uses S-expressions while the former uses hard-coded values.