Javascript:改进四个嵌套循环？

Question

我有一个包含嵌套数组的复杂对象数组。下面的工作是提取某些对象，但它是我写过的最丑陋的东西之一。

是否有一些 javascript 黑魔法可以优雅地做到这一点？

function getEighthInsertionBlocks() {
    var struct = Lifestyle.Pagination.structure;
    var blocks = [];
    for (var i = 0; i<struct.length; i++) {
        var page = struct[i];
        var layers = page.children;
        for (var j=0; j<layers.length; j++) {
            var layer = layers[j];
            if (layer.className === 'EighthPageLayer' ) {
                var rows = layer.children;
                for (var k=0; k<rows.length; k++) {
                    var row = rows[k];
                    eBlocks = row.children;
                    for (var l=0; l<eBlocks.length; l++) {
                        blocks.push(eBlocks[l]);
                    }
                }
            }
        }
    }

    return blocks;
}

并不是说我是 code golf 的忠实粉丝，而是......这太可怕了。

Answer 1

您可以编写一个通用迭代器，它将代码缩减为顺序 block :

var iterator = function(collection, callback){
    var length = collection.length;
    var results = [];
    var result;
    for (var i = 0; i < collection.length; i++){
        result = callback(colleciton[i], i);
        if (result){
            results = results.concat(result);
        }
    }
    return results;
};

function getEighthInsertionBlocks() {
    var struct = Lifestyle.Pagination.structure;
    var layers = iterator(struct, function(page){ return page.children; });
    var rows = iterator(layers, function(layer){
        return layer.className === 'EighthPageLayer' ? layer.children : null;
    });
    return iterator(rows, function(eBlocks, index){ return eblocks[index]; });
}