Is there a quick way to rebuild spell files from wordlists?

vim

Solution

I've solved this by adding the *.spl to the .gitignore file and then in the vimrc (which is also synced with GIT, add:

for d in glob('~/.vim/spell/*.add', 1, 1)
    if filereadable(d) && (!filereadable(d . '.spl') || getftime(d) > getftime(d . '.spl'))
        exec 'mkspell! ' . fnameescape(d)
    endif
endfor

source: https://vi.stackexchange.com/questions/5050/how-to-share-vim-spellchecking-additions-between-multiple-machines

This will cause vim to rebuild the .spl file each time the .add file has been updated when vim is started.

Problem

Is there any way to tell vim to update spell files for all languages listed in `'spelllang'` to pick up wordlist changes from outside of vim? I've started checking a wordlist file into git since I'm tired of adding the same words on multiple computers. I don't want to add the spell file to the git repo since merges would be ugly every time, but whenever I open vim, any recent updates are ignored until I do something from inside vim that rebuilds the spell file, such as `zg` to add a word to the dictionary.

Original source