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