Ecto.Type.embed_as
You're seeing just the callback
embed_as
, go back to Ecto.Type module for more information.
Specs
embed_as(format :: atom()) :: :self | :dump
Dictates how the type should be treated inside embeds.
By default, the type is sent as itself, without calling
dumping to keep the higher level representation. But
it can be set to :dump
so that it is dumped before
being encoded.