Thinking About JSON

JSON is a pretty simple idea. It was conceived in Javascript but can be used as data interchange between a multitude of languages (see the list here). JSON’s syntax consists of the following tokens: [ ]{ } : , and only 3 named tokens: false true null, and any number of whitespace between tokens.

example:

{
  "string" : "value",
  "number" : 5,
  "array" : ["one", "two"],
  "object" : { "string" : "value" }
}

While simple, the main thing to keep in mind is how your language translates some of the values.

• Javscript’s largest number is Number.MAX_VALUE = 1.7976931348623157e+308, so if you pass in a larger number then that, what happens is specific to your Javascript implementation. Check your implementation…I tried in Firefox and got Infinity.
• Also JSON does not parse binary data. You will have to base64 encode it.

Good exercise to do: JSON is usually sent with the whitespace removed. Create a function (in your favorite language) which takes a string which is a valid JSON object and pretty-print it. I’ll try to do it Javascript.