Ruby has leftward assignment (x = 3) and rightward assignment (3 => x). Now I give you, vertical assignment:
3
‖
x
That's right, this library provides a functioning vertical assignment operator. Yes it works, no it's not a good idea. It was built as an exploration of metaprogramming with Tracepoint and Ripper. This repo contains Bad Ideas™ and Ridiculous Code®. I've answered the question "can it be done?" but only you can answer the question "should it be done?" But as a hint: no. No it should not be done.
If you want a runthrough on how it works, check out my companion talk at RubyConf2021. I'll update this readme with a link to that talk on youtube when it's up. If you're reading this in, like, 2023, and there's still no link, I probably forgot.
You probably shouldn't get started. Getting started only ever leads to bad things; here more than ever.
But if you really must, you can require 'vequals', then call Vequals.enable, after which point the ‖ operator will "work"... if you can call it that.
vequals.rbcontains everything needed to use the vequals operator.minimized_vequals.rbis a stripped-down version of the same thing I made for the talk - no logging, no comments, etc.prep.rbis a file for manual testing. Go there and run that file if you want to play around with vequals.
There was a great version of vertical assignment created by one of the ruby core contributors. I can't find it right now because I'm on a plane with no wifi, but it was implemented in C as part of the core language and it was very nifty. You should go check that out.
Update: it's here, and of course is was by mame (Yusuke Endoh) https://bugs.ruby-lang.org/issues/17768