Getting basic information of a elixir project from GitHub

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7

The AST of a keyword list is not a keyword list by itself, so you cannot use Keyword to access things. AST is an abstraction of written code, and not of the data represented by that code. You’ll need more manual approaches for filtering out the information you need.

A rather naive appraoch to getting to the information you seek would be like this:

{_ast, acc} =
  Macro.postwalk(ast, %{version: nil, attributes: %{}}, fn
    {:@, _, [{name, _, value}]} = ast, acc when is_atom(name) and not is_nil(value) ->
      {ast, put_in(acc.attributes[name], value)}

    {:version, {:@, _, [{name, _, nil}]}} = ast, acc ->
      {ast, Map.put(acc, :version, {:attribute, name})}

    {:version, value} = ast, acc ->
      {ast, Map.put(acc, :version, value)}

    ast, acc ->
      {ast, acc}
  end)

acc
# %{attributes: %{version: ["0.0.7"]}, version: {:attribute, :version}}

However you’d want to be more cautious as currently any later keyword list with a :version key would overwrite the returned result.

What you’re doing here is very brittle, as you’re trying to interpret code without running it, which can easily break by someone not sticking to conventions closely.

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