Protocol.UndefinedError — Elixir v1.16.3

Search documentation of Elixir

# View Source Protocol.UndefinedError exception (Elixir v1.16.3)

An exception raised when a protocol is not implemented for a given value.

The following fields of this exception are public and can be accessed freely:

- `:protocol` (`module/0`) - the protocol that is not implemented
- `:value` (`term/0`) - the value that does not implement the protocol

For example, this code:

    Enum.at("A string!", 0)

would raise the following exception:

    %Protocol.UndefinedError{
      protocol: Enumerable,
      value: "A string!",
      # ...
    }