[
  {
    "_type": "_schemaType",
    "name": "ArrayView",
    "schema": {
       "type": "object",
       "extends": "View",
       "properties": {
          "arrayProp": { "type": "array" }
       }
     }
  },
  {
    "_type": "Reduce",
    "sourceType": "Human",
    "sourceKeyName": "lastName",
    "targetType": "ArrayView",
    "add": " \
      function add(key, previous, value) { \
        if (!previous) previous = { firstNames: [] } \
        previous.firstNames.push(value.firstName); \
        return previous; \
      } ",
    "subtract": " \
      function subtract(key, previous, value) { \
        var idx; \ 
        if ((idx = previous.firstNames.indexOf(value.firstName)) >= 0) \
          previous.firstNames.splice(idx, 1); \
        return previous; \
      } " 
  },
  {
    "_type": "Human",
    "firstName": "Bob",
    "lastName": "Smith"
  },
  {
    "_type": "Human",
    "firstName": "Hank",
    "lastName": "Jones"
  },
  {
    "_type": "Human",
    "firstName": "Roger",
    "lastName": "Smith"
  },
  {
    "_type": "Human",
    "firstName": "Julio",
    "lastName": "Jones"
  }
]