javascript - Error extending entity with a observableArray in Breeze via constructor -

if try extend entity in breeze via constructor like:

breeze.entitymanager('serviceurl').metadatastore.registerentitytypector(   'customer',   function () {     this.orders = ko.observablearray([]);   } ); 

i knockout error when trying set new properties:

mycustomer.orders(neworders); 

the error is:

"cannot write value ko.computed unless specify 'write' option. if wish read current value, don't pass parameters." 

the same work if add in post-construction initializer. doing wrong?

you missing required parameter -

breeze.entitymanager('serviceurl').metadatastore.registerentitytypector(   'customer', null,   function () {     this.orders = ko.observablearray([]);   } ); 

your 'customer' parameter required identify entity type.

the second parameter constructor (not extending properties onto entity)

the third initializing entity

http://www.breezejs.com/sites/all/apidocs/classes/metadatastore.html#method_registerentitytypector

you need define entity in function -

breeze.entitymanager('serviceurl').metadatastore.registerentitytypector(   'customer',   function (cust) {     cust.orders = ko.observablearray([]);   } );