使用Enum.map的意外行为 - 仅接受匿名函数

Question

我有List Tuples：

golden = [{%{"age" => 80, "name" => "Dorothy"}, 
           %{"age" => 50, "name" => "Rose"}},
          {%{"age" => 90, "name" => "Sophia"},
           %{"age" => 60, "name" => "Blanche"}}]

方法＃1

我使用Enum.map如下，但收到错误：

Enum.map(golden, Tuple.to_list)

** (UndefinedFunctionError) undefined function Tuple.to_list/0
(elixir) Tuple.to_list()

方法＃2

当我定义匿名函数时：

f = fn(data) -> Tuple.to_list(data) end

并使用Enum.map，我得到了理想的结果：

Enum.map(golden, f)

[[%{"age" => 80, "name" => "Dorothy"}, %{"age" => 50, "name" => "Rose"}],
 [%{"age" => 90, "name" => "Sophia"}, %{"age" => 60, "name" => "Blanche"}]]

也许我错过了一些东西，但这两种方法不完全相同吗？

Answer 1

您遗失& operator Capture operator：

  

捕获或创建匿名函数。

iex()> Enum.map(golden, &Tuple.to_list/1)
[[%{"age" => 80, "name" => "Dorothy"}, %{"age" => 50, "name" => "Rose"}],
 [%{"age" => 90, "name" => "Sophia"}, %{"age" => 60, "name" => "Blanche"}]]