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elixir-metaprogramming.md

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+---
+title: Elixir metaprogramming
+category: Elixir
+---
+
+## Kernel
+
+Most of these magic is defined in [Kernel.SpecialForms](http://devdocs.io/elixir/elixir/kernel.specialforms).
+
+### Pseudo-variables
+
+```elixir
+__DIR__     # current dir
+__MODULE__  # current module
+__CALLER__  # caller of the function
+```
+
+### [`__ENV__`](http://devdocs.io/elixir/elixir/kernel.specialforms#__ENV__/0)
+
+```elixir
+Map.keys(__ENV__)
+[:__struct__, :aliases, :context, :context_modules, :export_vars, :file,
+ :function, :functions, :lexical_tracker, :line, :macro_aliases, :macros,
+ :module, :requires, :vars]
+```
+
+```elixir
+__CALLER__.module |> Module.definitions_in |> IO.inspect
+```
+
+```elixir
+apply(Enum, :reverse, [[1, 2, 3]])
+```