Relaxed JSON (RJSON)

RJSON (Relaxed Javascript Object Notation) allows for concise and succinct JSON authoring and parsing.

Download the official NPM Package here: https://www.npmjs.com

In the spirit of the original JSON, there are only a few simple rules.

• All standard JSON is valid. See json.org for the specification.
• Commas are optional between objects pairs and array items.
• Trailing commas are allowed.
• Quotes are optional around simple-keys and simple-values.
• Single-quote pairs, double-quote pairs, and backtick pairs can be used for strings.
• Single-line and multi-line comments are allowed.
• Multiline strings are allowed.

Our flavor of RJSON goes beyond other variants, including JSON5. You can try the online demo here.

Table Of Contents

• The Bottom Line
• Commas
• Quotes
  • Single, Double, or Backtick Quotes
  • Optional Quotes
    • No quotes are needed around simple-keys
    • No quotes are needed around simple-values
  • Multline Strings
  • Special Considerations
    • Reserved Characters
    • Reserved Words
    • Escaped Characters
• Comments

The Bottom Line

• Leave out the commas.
• An object-key must be in quotes if:
  • It contains an unescaped reserved character
  • It contains // or /*
• A string-value must be in quotes if:
  • It contains an unescaped reserved character.
  • It contains // or /*
  • The string true, false, or null is needed.
  • The string representation of a number is needed.

Relax, it's simple!

Commas

Commas are optional between object key-value pairs and array items.

[
    "one" 
    "two"
    "three"
]

{
    "one" : "1"
    "two" : "2"
    "three" : "3"
}

[
    {
        "one" : "1"
        "two" : "2"
    }
    {
        "three" : "3"
        "four" : "4"
    }
    "five"
    "six"
]

If you are a comma lover, trailing commas are allowed.

[ 1, 2, 3, ]

{a:1, b:2, c:3,}

Quotes

Single, Double, or Backtick Quotes

Both single-quote and double-quote pairs are valid in RJSON. The opposite quote character does not need to be escaped.

[
    "Hello world"
    'Hello world'
    `Hello world`
    "He said 'What'?"
    'He said "What"?'
    'A "double" and \'single\' quote'
    "A \"double\" and 'single' quote"
    `This has unescaped " and ' in the string`
]

Optional Quotes

No quotes are needed around simple-keys

If a key does not contain an unescaped reserved character, it is a simple-key and does not require quotes. Reserved words (numbers and the values true, false, and null are always interpreted as strings when used as an object key.

{
    1 : one
    2 : two
    true : "the key is the string true"
    escape\:me : "the key has an escaped reserved character (not recommended)"
    a\ space : "the key has an escaped space (not recommended)"
}

No quotes are needed around simple-values

If a value does not contain an unescaped reserved character, and is not a reserved word, it is a simple-value and does not require quotes.

[ milk, eggs, fruit, 'candy bars' ]

or even better, lose the commas:

[ milk eggs fruit 'candy bars' ]

using escape (not recommended):

[ milk eggs fruit candy\ bars ]

Multline Strings

A string can continue to a new line if the line ends with a '\'.

"A string \
on 3 \
lines"

'Another string \
on 3 \
lines'

{ aKey : "A string value \
on 3 \
lines"
}

Special Considerations

Reserved Characters

Keys and values containing these characters must either be:

• inside quotes
• escaped with the '\' prefix.

  [ ] { } , : " ' ` whitespace

[
    a-simple-string
    another_simple_string
    a\ string\ with\ escaped\ spaces
    a_string_with_a_\,(comma)
]

We recommend using quotes instead of escaped characters, especially for spaces.

[
    'a string with escaped spaces'
    'a_string_with_a_,(comma)'
]

Reserved Words

These word sequences must be quoted when used as a string value:

true false null <any-parsable-number> // /*

If a simple-value can be parsed as a number, it will become a JSON number.

{ number: 1.0}

will become

{ "number" : 1 }

A simple-key will always be parsed as a string, even if it is a number or reserved word.

{ 1:1, true:true } 

will become

{ "1":1, "true":true }

Escaped Characters

Reserved Characters can be escaped with a '\' to avoid using quotes. We do not recommend this as a general rule however.

[ it\:em item\ with\ spaces]

[ "it:em",  "item with spaces"]

Comments

Both single-line and multi-line comments are allowed. Comments use Java/Javascript conventions. See Mozilla-Comments for the specification.

/* This is an 
RJSON file */

{ shopping-list: [ milk butter /* don't forget the beer */ beer ] } // This is a shopping list.