An Introduction to Lookaround Regular Expression in Neovim/Vim

Today I want to use some regular expressions for searching and replacing in my files. But I found that Nvim/Vim regular expression engine has its own flavor, which is different from the regex engine used by Sublime Text¹. I ended up learning some of the basics of Nvim-style regex. In this post, I want to share about how to use lookaround² in Nvim.