On "Why Elixir?"

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Maybe a “best practices” guidelines for eval and rpc might be useful. One of my eval statements in my shell script looks like this, which I think is maybe evocative of some of the struggles:

#/bin/sh
my_app/bin/my_app eval "import IP; Application.ensure_all_started(:my_app); :some_atom1; :some_atom2; MyApp.run_file('~/configuration.toml', ~i/$1/);"
  • I’m not sure there’s guidance about sometimes needing to do Application.ensure_all_started/1 in an eval statement; I only knew immediately to put that in from lots of experience, and this may be frustrating for beginners.
  • the :some_atoms are there because i have been maybe overly cautious about String.to_existing_atom.
  • the first parameter to run_file/2 is a charlist to avoid having to escape double quotes, and is a bit of a hack because I happened to remember run_file just calls File.read!, which admits charlists.
  • the second parameter uses this sigil_i that I happened to remember I’d written because that lets me avoid a quotation mark in IP.from_string!/1. If I had a function that took a String, I would probably want to use ~s// or something, but guidance on that as a best practice would be nice.

It might also be nice to be able to package shell/batch scripts into the release relatively easily in the Release pipeline (like how we have :assemble and :tar directives) I don’t do this currently (and just copy/paste from my source directory into vi).

That said, I love releases. I did a release on a personal project - persistent websocket datascraping into Sqlite last night directly onto an free-tier aws. Smooth as a baby.

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