Initial upload

elixir/take-a-number/HINTS.md

@@ -0,0 +1,40 @@
+# Hints
+
+## General
+
+- Read about processes in the official [Getting Started guide][getting-started-processes].
+- Read [this blog post][mullen-processes] about Elixir processes.
+
+## 1. Start the machine
+
+- The machine should run in a new process. There is [a built-in function that starts a new process][kernel-spawn-1].
+- You will need another function that the new process will execute.
+
+## 2. Report the machine state
+
+- The machine's process needs to respond to messages.
+- There is [a built-in function that waits for a message to arrive in the process's mailbox][kernel-receive].
+- There is [a built-in function that sends a message to another process][kernel-send].
+- Use recursion to wait for more than one message.
+- Pass the machine's state as an argument to the recursive function.
+
+## 3. Give out numbers
+
+- This step is conceptually the same as the previous step. The only difference is the need to update the machine's state.
+
+## 4. Stop the machine
+
+- This step doesn't require sending any messages as a response.
+- A process will exit if it has no more code to execute.
+- This is a base case of the recursive function.
+
+## 5. Ignore unexpected messages
+
+- This step doesn't require sending any messages as a response.
+- You can use `_` to match all messages that didn't match previous patterns.
+
+[getting-started-processes]: https://elixir-lang.org/getting-started/processes.html
+[mullen-processes]: https://samuelmullen.com/articles/elixir-processes-send-and-receive/
+[kernel-spawn-1]: https://hexdocs.pm/elixir/Kernel.html#spawn/1
+[kernel-receive]: https://hexdocs.pm/elixir/Kernel.SpecialForms.html#receive/1
+[kernel-send]: https://hexdocs.pm/elixir/Kernel.html#send/2