angular - rxjs fromPromise does not exist on type Observable -

in angular 2 using rxjs trying convert promise observable. many of online guides showed used frompromise on observable. throws error:

property 'frompromise' not exist on type 'typeof observable'. 

observable imported like:

import { observable } "rxjs/observable"; 

trying import frompromise other operators results in error:

import 'rxjs/add/operator/frompromise'; 

even if suppress typescript error still results in error:

(<any>observable).frompromise 

error:

uncaught (in promise): typeerror: __webpack_imported_module_3_rxjs_observable__.observable.frompromise not function 

somewhat similar issue reported on rxjs repo here there no solution there either.

frompromise can used static method or can patched observable prototype.

for first, can following:

import { frompromise } 'rxjs/observable/frompromise';  var observablefrompromise = frompromise(promisesrc); 

more info approach here

to second, need change import statement:

import { observable } 'rxjs/observable'; import 'rxjs/add/observable/frompromise';  var observablefrompromise = observable.frompromise(promisesrc); 

more info approach here

personally recommend first one, considering 2nd approach 1rst, difference observable prototype changed.