Why doesn't `brew install --cask --HEAD emacs` give me the latest GUI Emacs?

Question

for macOS
What if I want the latest emacs, and gui too, why isn't "brew install --cask --HEAD emacs" allowed?

I get: Error: Invalid usage: Options --cask and --HEAD are mutually exclusive.

Answer 1

This is a question about a tool called brew, which is not part of Emacs. You should ask for help with this tool in a forum dedicated to the tool.