Coffeescript是否支持嵌套列表推导？

Question

例如，给定以下结构

    pages = [
        [
            { myvar: 1},
            { myvar: 2},
            { myvar: 3},
        ]
    ];

我如何表达愚蠢（类似python）的理解？

v.myvar for p in pages for v in p

Answer 1

AFAIK，您不能，请参阅：https://github.com/jashkenas/coffee-script/issues/1191

同时解决方法（直到CoffeeScript得到改进）：

pages = [
        [
            { myvar: 1},
            { myvar: 2},
            { myvar: 3},
        ]
    ];

result = []
for row in pages
  for map in row
    result.push map.myvar

console.log result

输出：

[ 1, 2, 3 ]