[JAVASCRIPT] 배열의 중복값 필터 하기

function f_getUniqueArray(data, groupStr){
		var uniqueNames =[];
		$.each(data, function(index, item){
			var group = item[groupStr]; //21
			if($.inArray(group, uniqueNames) === -1) uniqueNames.push(group);
		})
		
		return uniqueNames;
    }

data = Array값 groupStr 필터랑 할 데이터

ex) data = [
{name='A', date='2019'},
{name='B', date='2019'},
{name='C', date='2019'},
{name='D', date='2019'},
{name='E', date='2019'},
{name='F', date='209'}, ];
groupStr = 'date';

return 값 : uniqueNames = [{date='2019'},{date='2018'}]