         sortBy:     type: 'any'
         component:  type: 'function'
         onColumnClick: type: 'function'
+        fetchIndex: type: 'integer'
 
     derived:
         default_value: deps: ['id'], fn: ->

        )
        super
        @visible = @subcollection(where: {visible: true})


class Operator extends Lanes.Models.Base
    registerForPubSub: false

            deps: ['model_field'], fn: ->
                type = @model_field?.type || 'string'
                if type == "code" then "string" else type

    validValue: (value) ->
        if this.type == 'n'
