hjson-js

Hjson, the Human JSON. A configuration file format that caters to humans and helps reduce the errors they make.

{
  # specify rate in requests/second (because comments are helpful!)
  rate: 1000

  // prefer c-style comments?
  /* feeling old fashioned? */

  # did you notice that rate doesn't need quotes?
  hey: look ma, no quotes for strings either!

  # best of all
  notice: []
  anything: ?

  # yes, commas are optional!
}

The JavaScript implementation of Hjson is based on JSON-js. For other platforms see hjson.org.

Install from npm

npm install hjson

Usage

var Hjson = require('hjson');

var obj = Hjson.parse(hjsonText);
var text2 = Hjson.stringify(obj);

To keep comments intact see API.

From the Commandline

Install with npm install hjson -g.

usage: hjson [OPTIONS] [INPUT]

  hjson can be used to convert JSON from/to Hjson.

  hjson will read the given JSON/Hjson input file or read from stdin.
  - default: will output as Hjson.
    - with -sl: will output the opening brace on the same line.
    - with -root: will output braces for the root object.
    - with -quote: will quote all strings.
  - with -j or -json: will output as formatted JSON.
  - with -c or -json=compact: will output as JSON.

Sample:

• run hjson test.json > test.hjson to convert to Hjson
• run hjson -j test.hjson > test.json to convert to JSON

API

The API is the same for the browser and node.js version.

Hjson.parse(text, options)

This method parses JSON or Hjson text to produce an object or array.

• text: the string to parse as JSON or Hjson
• options: object
  • keepWsc: boolean, keep white space and comments. This is useful if you want to edit an hjson file and save it while preserving comments (default false)

Hjson.stringify(value, options)

This method produces Hjson text from a JavaScript value.

• value: any JavaScript value, usually an object or array.
• options: object
  • keepWsc: boolean, keep white space. See parse.
  • bracesSameLine: boolean, makes braces appear on the same line as the key name. Default false.
  • quotes: string, controls how strings are displayed.
    • "min": no quotes whenever possible (default)
    • "always": always use quotes
  • space: specifies the indentation of nested structures. If it is a number, it will specify the number of spaces to indent at each level. If it is a string (such as '\t' or ' '), it contains the characters used to indent at each level.
  • eol: specifies the EOL sequence (default is set by Hjson.setEndOfLine())

Hjson.endOfLine(), .setEndOfLine(eol)

Gets or sets the stringify EOL sequence ('\n' or '\r\n'). When running with node.js this defaults to os.EOL.

Hjson.rt { parse, stringify }

This is a shortcut to roundtrip your comments when reading and updating a config file. It is the same as specifying the keepWsc option for the parse and stringify functions.

modify & keep comments

You can modify a Hjson file and keep the whitespace & comments intact (round trip). This is useful if an app updates its config file.

// parse, keep whitespace and comments
// (they are stored in a non enumerable __WSC__ member)
var data = Hjson.rt.parse(text);

// modify like you normally would
data.foo = "text";

// you can also edit comments by accessing __WSC__
var wsc = data.__WSC__;
// __WSC__ for objects contains { c: {}, o: [] }
// - c with the actual comment and
// - o (array) with the order of the members
wsc.c.hugo = "just another test";
wsc.o.splice(2, 0, "hugo");
data.hugo = "value";

data.arrayWithComments = [ "a" ];
// __WSC__ for arrays is just an array with the
// comments ([0] for the space before the elements)
data.arrayWithComments.__WSC__ = [ "before a", "after a" ];

// convert back to Hjson
console.log(Hjson.rt.stringify(data));

History

see history.md