Override Vim's filetype setting for octave

Question

GNU Octave and Matlab share the .m suffix, but Octave's syntax is a little different, like allowing # as a comment.

I created a scripts.vim, but that does not get called since the filetype is already set to Matlab.

That is the snippet that I use, it works, but it never gets executed in ~/.vim/scripts.vim or if I put it into ~/.vim/ftdetect/octave.vim

if getline(1) =~ '^#!/.*octave'                                        
    set filetype=octave
endif

Where can I set this code?

Answer 1

I got it to work with the filetype.vim now:

" ~/.vim/filetype.vim

if exists("did_load_filetypes")
    finish
endif

function! DetectOctave()
    echom getline(1)
    if getline(1) =~ '^#!/.*octave.*'                                        
        set filetype=octave
    endif
endfunction

augroup filetypedetect
    au! BufRead,BufNewFile *.m  call DetectOctave()
augroup END