I went back to building on ruby during an interview and I was asked to explain symbols. It got me thinking about ruby symbols and elixir atoms. One of the big differences between ruby symbols and elixir atoms is that atoms aren’t garbage collected and thus there is a possibility of atom exhaustion.

I went further and learned that in the older ruby days(ruby < 2.2) there was also a possibility of symbol exhaustion(https://stackoverflow.com/questions/16621073/when-to-use-symbols-instead-of-strings-in-ruby).

So my question is still why aren’t atoms GC’d. My first thought is because module names and some keywords like false, true and nil are internally represented as atoms it is better to have them in memory the whole time. But that doesn’t seem correct to me.

And is there a way to manually free an atom once it has been declared and you are sure it is no longer being used?