Clojurescript protocol usage?

Question

Taking a first stab at using protocols in ClojureScript. Following is the protocol definition/implementation:

(defprotocol IDataTable
  (-pages [this])
  (-cnt! [this cnt])
  (-paginate [this])
 )

(deftype DataTable [id url info]
 IDataTable
 (-cnt! [_ cnt] (swap! info (fn [v] (assoc v :cnt cnt))) )
 (-pages [_]
   (inc (.round js/Math (/ (:cnt @info) (:length @info))))
 )

(-paginate [_]
  (let [arr (take 5 (drop (- (:page @info) 1) (range 1 (pages))))]
   (c/paging id (flatten ["Prev" arr "Next"]) )
  ))
 )

I am confused on how to invoke the functions defined in the protocol.

Following is the code to instantiate:

(def table-id "some-table")
(def paging (atom {:page 1 :length 10 :cnt 0  }))
(def data-table (DataTable. table-id "/list/data" paging))

The above code works and can access the properties using the following form:

(js/alert (.-id data-table))

The problem I am facing is how to invoke the functions defined in the protocol. The following forms result in error (runtime).

 (-cnt! data-table 10) ;; Error: -cnt! is not a method
 (.-cnt! data-table 10) ;; Error

Browsed the generated Javascript code, its got long-winded names for functions.

Thanks

EDIT: Think I found the answer. Looks like I need supporting functions in the namespace.

(defn cnt! [t cnt]
   (when (satisfies? IDataTable t)
     (-cnt! t cnt))
 )

With the function defined above, am able to access the functions. Wonder if this is the right approach?

EDIT2: Well, with further analyzing the generated javascript code realized one doesn't need helper functions as the above edit, the function calls needs to prefixed with namespace:

 (:require [table :as tbl])

(def table-id "some-table")
(def paging (atom {:page 1 :length 10 :cnt 0  }))
(def data-table (DataTable. table-id "/list/data" paging))

 (tbl/-cnt! data-table 10) ;; Works!!!

Answer 1

Looks like you answered your own question, but in case anyone ends up here...

Protocol methods are automatically promoted to the namespace that they are declared in, this means if you want to call those functions you call them as if they are regular functions in the namespace.