enum

Enum can be declared as any internal type.

If none of value are matched while parsing { :wrong_data, _wrong_data_bin } will be returned for such struct. This is playing nicely with dynamic variant dispatching, same as you would expect for static_value.

Here’s an example:

Integer based

  iex> defmodule EnumInteger do
  ...>   use BinStruct
  ...>   field :value, {
  ...>    :enum,
  ...>    %{
  ...>     type: :uint16_le,
  ...>     values: [
  ...>      {0x0004, :high_color_4bpp},
  ...>      {0x0008, :high_color_8bpp}
  ...>     ]
  ...>    }
  ...>  }
  ...> end
  ...>
  ...> EnumInteger.new(value: :high_color_4bpp)
  ...> |> EnumInteger.dump_binary()
  ...> |> EnumInteger.parse()
  ...> |> then(fn {:ok, struct, _rest } -> struct end)
  ...> |> EnumInteger.decode()
  %{ value: :high_color_4bpp }
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Binaries based

  iex> defmodule EnumBinaries do
  ...>   use BinStruct
  ...>   field :value, {
  ...>    :enum,
  ...>    %{
  ...>     type: :binary,
  ...>     values: [
  ...>      { "A" , :high_color_4bpp},
  ...>      { "B", :high_color_8bpp}
  ...>     ]
  ...>    }
  ...>  }, length: 1
  ...> end
  ...>
  ...> EnumBinaries.new(value: :high_color_4bpp)
  ...> |> EnumBinaries.dump_binary()
  ...> |> EnumBinaries.parse()
  ...> |> then(fn {:ok, struct, _rest } -> struct end)
  ...> |> EnumBinaries.decode()
  %{ value: :high_color_4bpp }
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