Sometimes when I am working on a project, I use project-wide variable or function definition. So I name them. I usually suck at naming. So when I think of a better name, I need a way to change it globally, ie in all the files of the current project that uses it. In Spacemacs, I have heard of what Fabien Dubosson, one of the main Spacemacs dev, called the “nuclear weapon of multi-editing”. When I s