Implementing a Protocol
The defimpl macro lets you give Elixir the implementation of a protocol for one or more types. The code that follows is the implementation of the Inspect protocol for PIDs and references.
| | defimpl Inspect, for: PID do |
| | def inspect(pid, _opts) do |
| | "#PID" <> iolist_to_binary(pid_to_list(pid)) |
| | end |
| | end |
| | |
| | defimpl Inspect, for: Reference do |
| | def inspect(ref, _opts) do |
| | '#Ref' ++ rest = :erlang.ref_to_list(ref) |
| | "#Reference" <> iolist_to_binary(rest) |
| | end |
| | end |
Finally, the Kernel module implements inspect, which calls Inspect.inspect with its parameter. This means that when you call inspect(self), it becomes a call to Inspect.inspect(self). And because self is a PID, this in turn ...
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