数组中对象元素去重

var arr = [
    {currency: 'GBP', total: 10},
    {currency: 'GBP', total: 10},
    {currency: 'JPY', total: 11},
    {currency: 'GBP', total: 10},
    {currency: 'GBP', total: 25},
    {currency: 'EUR', total: 16},
    {currency: 'GBP', total: 10},
    {currency: 'GBP', total: 10}
];
var arr1 = [];
// 按币种分类汇总金额，参数：要分类的数组、分好类要返回的新数组
function classify(arr, arr1) {
    var temp = {};
    for (var j in arr) {
        var key = arr[j].currency;
        if (temp[key]) {
            temp[key].total = temp[key].total + arr[j].total;
        } else {
            temp[key] = {};
            temp[key].total = arr[j].total;
        }
    }
    angular.forEach(temp, function(v, k) {
        arr1.push({
            currency: k,
            total: v.total
        });
    });
    return arr1;
}

classify(arr, arr1);

console.log('处理前：', arr);
console.log('处理后：', arr1);