Allows a knockout model to be updated with fresh data composed by an object with the same structure as the viewmodel

ko.updateModel

ko.updateModel = (model, data, path, callback) ->
  isObject = (obj) ->
    typeof obj is 'object' and !Array.isArray obj

  return if not isObject data
  
  callbackIsFunction = (typeof callback) is 'function'
  
  for k, v of data
    branchPath = path + "." + k
    
    if isObject(v) ## Object, recursive call
      ko.updateModel model, v, branchPath, callback
    else ## Data, fill the model
      type = eval "typeof model" + branchPath
      
      ### There is no equivalent in the model ###
      if type is 'undefined'
	if callbackIsFunction
	  eval "model" + branchPath + " = callback(v, branchPath)"
	else
	  eval "model" + branchPath + " = v"
      
      ## Observable if function, check
      else if type is 'function'
	isWritable = eval "ko.isObservable(model" + branchPath + ")" &&
	  eval "ko.isWritableObservable(model" + branchPath + ")"
	## ignore the value if is not an observable / writable
	eval "model" + branchPath + "(v)" if isWritable
      
      ## Assume pure value if not a function
      else
	eval "model" + branchPath + " = v"