dist/vendor.js
function distinctUntilKeyChanged(key, compare) {
	    return distinctUntilChanged_1.distinctUntilChanged.call(this, function (x, y) {
	        if (compare) {
	            return compare(x[key], y[key]);
	        }
	        return x[key] === y[key];
	    });
	}
function distinctUntilKeyChanged(key, compare) {
	    return distinctUntilChanged_1.distinctUntilChanged.call(this, function (x, y) {
	        if (compare) {
	            return compare(x[key], y[key]);
	        }
	        return x[key] === y[key];
	    });
	}
function distinctUntilKeyChanged ( key , compare ) { return distinctUntilChanged_1 . distinctUntilChanged . call ( this , function ( x , y ) { if ( compare ) { return compare ( x [ key ] , y [ key ] ) ; } return x [ key ] === y [ key ] ; } ) ; }
Returns an Observable that emits all items emitted by the source Observable that are distinct by comparison from the previous item,
using a property accessed by using the key provided to check if the two items are distinct.
If a comparator function is provided, then it will be called for each item to test for whether or not that value should be emitted.
If a comparator function is not provided, an equality check is used by default.
@param {string} key string key for object property lookup on each item.
@param {function} [compare] optional comparison function called to test if an item is distinct from the previous item in the source.
@return {Observable} an Observable that emits items from the source Observable with distinct values based on the key specified.
@method distinctUntilKeyChanged
@owner Observable
Returns an Observable that emits all items emitted by the source Observable that are distinct by comparison from the previous item using a property accessed by using the key provided to check if the two items are distinct . If a comparator function is provided then it will be called for each item to test for whether or not that value should be emitted . If a comparator function is not provided an equality check is used by default .