///
module Rx {
export interface Observable {
/**
* Searches for an element that matches the conditions defined by the specified predicate, and returns the first occurrence within the entire Observable sequence.
* @param {Function} predicate The predicate that defines the conditions of the element to search for.
* @param {Any} [thisArg] Object to use as `this` when executing the predicate.
* @returns {Observable} An Observable sequence with the first element that matches the conditions defined by the specified predicate, if found; otherwise, undefined.
*/
find(predicate: _Predicate, thisArg?: any): Observable;
}
}
(function () {
var o : Rx.Observable;
o = o.find((x) => true);
o = o.find((x) => true, {});
});