prettyJson.js

function prettyJson(data) {
	var json = JSON.stringify(data, null, "\t");
	function compactJson(json) {
		try {
			var compact = JSON.stringify(JSON.parse(json));
			var parts = compact.split('"');
			for (var i = 0; i < parts.length; i++) {
				var part = parts[i];
				part = part.replace(/:/g, ': ');
				part = part.replace(/,/g, ', ');
				parts[i] = part;
				i++;
				while (i < parts.length && parts[i].charAt(parts[i].length - 1) == "\\") {
					i++;
				}
			}
			return parts.join('"');
		} catch (e) {
			return json;
		}
	}
	
	json = json.replace(/\{[^\{,}]*\}/g, compactJson); // Objects with a single simple property
	json = json.replace(/\[[^\[,\]]*\]/g, compactJson); // Arrays with a single simple item
	json = json.replace(/\[[^\{\[\}\]]*\]/g, compactJson); // Arrays containing only scalar items
	return json;
}