module Concurrent::Concern::Dereferenceable

Object references in Ruby are mutable. This can lead to serious problems when the ‘#value` of a concurrent object is a mutable reference. Which is always the case unless the value is a `Fixnum`, `Symbol`, or similar “primitive” data type. Most classes in this library that expose a `#value` getter method do so using the `Dereferenceable` mixin module.

@!macro copy_options