Protocol for encoding values for LiveSvelte JSON serialization.

Transforms structs and other terms into JSON-compatible data (maps, lists, primitives) before the configured JSON library encodes to a string. Supports @derive with :only and :except to control which struct fields are encoded. By default all keys except :__struct__ are encoded.

Deriving

• @derive LiveSvelte.Encoder — encode all struct fields except :__struct__
• @derive {LiveSvelte.Encoder, only: [:a, :b]} — encode only listed keys
• @derive {LiveSvelte.Encoder, except: [:secret]} — encode all except listed keys

Example

defmodule User do
  @derive {LiveSvelte.Encoder, except: [:password]}
  defstruct [:name, :email, :password]
end

For structs you don't own, use Protocol.derive/3 outside the module.