Eml.Data protocol

The Eml Data protocol.

This protocol is used by Eml.to_content/3 function to convert different Elixir data types to Eml content.

You can easily implement a protocol implementation for a custom type, by defining a to_eml function that receives the custom type and outputs to eml.

Example

iex> defmodule Customer do
...>   defstruct [:name, :email, :phone]
...> end
iex> defimpl Eml.Data, for: Customer do
...>   def to_eml(%Customer{name: name, email: email, phone: phone}) do
...>     use Eml.Language.HTML
...>
...>     div [class: "customer"] do
...>       div [span("name: "), span(name)]
...>       div [span("email: "), span(email)]
...>       div [span("phone: "), span(phone)]
...>     end
...>   end
...> end
iex> div %Customer{name: "Fred", email: "freddy@mail.com", phone: "+31 6 5678 1234"}
#div<[#div<%{class: "customer"}
 [#div<[#span<["name: "]>, #span<["Fred"]>]>,
  #div<[#span<["email: "]>, #span<["freddy@mail.com"]>]>,
  #div<[#span<["phone: "]>, #span<["+31 6 5678 1234"]>]>]>]>

Note that you can’t directly render a custom type, as the Eml.Data protocol is not used during rendering. If you want to directly render a custom type, convert it to eml content first:

%Customer{name: "Fred", email: "freddy@mail.com", phone: "+31 6 5678 1234"} |> Eml.to_content |> Eml.render
# => "<div class='customer'><div><span>name: </span><span>Fred</span></div><div><span>email: </span><span>freddy@mail.com</span></div><div><span>phone: </span><span>+31 6 5678 1234</span></div></div>"