Using symbols is Thread Safe in Rails ?
I read a good article about Thread Safe in Rails. Here is the [link](https://bearmetal.eu/theden/how-do-i-know-whether-my-rails-app-is-thread-safe-or-not/). One thing that I couldn't wrap my head is his example about Class instance variables. My doubt is how just using a symbol becomes thread safe that block of code. Please let me know your thoughts.