Emacs does this. See https://emacs.stackexchange.com/questions/2364/what-is-the-function-purecopy-needed-for https://emacs.stackexchange.com/questions/2364/what

Emacs does this. See https://emacs.stackexchange.com/questions/2364/what-is-the-function-purecopy-needed-for https://emacs.stackexchange.com/questions/2364/what-is-the-f...