The action closure (somewhat similar to the map closure) applies an action closure to every element of a List.

action闭包(与map闭包有点相似)把action闭包应用于List的每个元素。

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In Listing 7, we've taken things one step further by currying the map closure, resulting in a block that will multiply all the elements of a given list by 12.

在清单7中，我们把事情又向前进行了一步，对map闭包进行了curry处理，形成一个块，会将指定列表中的所有元素都乘以12。

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