defmodule Consultant do
def file(path) do
with {:ok, data} <- File.read(path), do: string(data)
end
def string(input) do
with {:ok, quoted} <- Code.string_to_quoted(input), do: {:ok, parse(wrap(quoted))}
catch
{:error, _} = error -> error
end
defp wrap({:__block__, _, data}), do: data
defp wrap(data), do: [data]
defp parse(data) when is_number(data) when is_binary(data) when is_atom(data),
do: data
defp parse(list) when is_list(list) do
Enum.map(list, fn
{k, v} -> {parse(k), parse(v)}
other -> parse(other)
end)
end
defp parse({:%{}, _, data}) do
for {key, value} <- data, into: %{}, do: {parse(key), parse(value)}
end
defp parse({:{}, _, data}) do
data
|> Enum.map(&parse/1)
|> List.to_tuple()
end
defp parse({:__aliases__, _, names}), do: Module.concat(names)
defp parse({:sigil_W, _meta, [{:<<>>, _, [string]}, mod]}), do: word_sigil(string, mod)
defp parse({:sigil_R, _meta, [{:<<>>, _, [string]}, mod]}),
do: Regex.compile!(string, List.to_string(mod))
defp parse({sigil, meta, _data} = quoted) when sigil in ~w[sigil_w sigil_r]a do
line = Keyword.get(meta, :line)
throw({:error, {:illegal_sigil, line, quoted}})
end
defp parse({_, meta, _} = quoted) do
line = Keyword.get(meta, :line)
throw({:error, {:invalid, line, quoted}})
end
defp word_sigil(string, []), do: word_sigil(string, 's')
defp word_sigil(string, [mod]) when mod in 'sac' do
parts = String.split(string)
case mod do
?s -> parts
?a -> Enum.map(parts, &String.to_atom/1)
?c -> Enum.map(parts, &String.to_charlist/1)
end
end
end
I need to make it as a library or submit it to the core (but it would probably be rejected in favour of mentioned library).
Just beware that this will not support values like 1 + 2 as this format require all values to be constant (however adding support for some simple computations shouldn’t be that hard).
