====== Notepad++ ======

  * Replace all spaces between UPPERCASE words with "_"<code>Find what: ([A-Z])\s(?=[A-Z])
Replace with: \1_
Match case</code>Also see [[https://www.regular-expressions.info/lookaround.html|Regex Lookahead]] and [[https://stackoverflow.com/questions/19801351/what-is-a-regular-expression-for-removing-spaces-between-uppercase-letters-but|What is a regular expression for removing spaces between uppercase letters, but keeps spaces between words?]]