Abusing monadic do notation library for generating JSON object. Hard-binded to json package from hackage. Main ideas

• Overloaded function field, that may set values of fields of different types - Bool, Int, String, lists etc.
• Internal IO - value of the field can be IO a, is we know how to put a into JSON. That means that there is no need to do prebinding
• Compositionality - value of field can also be fields. Easy to do embeded objects
• Monadic notation - it really looks nicer then composition with . or some magic combinator

 json $ do
     field "a" "a"
     field "b" [1,2,3]
     field "c" $ do
         field "x" True
         field "y" False

Will generate json object {a : a, b: [1,2,3], c: {x: true, y : false}}