How can you automatically remove trailing whitespace in vim

Question

I am getting \'trailing whitespace\' errors trying to commit some files in git.

I want to remove these trailing whitespace characters automatically right before I sa

Answer 1

I both highlight existing trailing whitespace and also strip trailing whitespace.

I configure my editor (vim) to show white space at the end, e.g.

with this at the bottom of my .vimrc:

highlight ExtraWhitespace ctermbg=red guibg=red
match ExtraWhitespace /\s\+$/
autocmd BufWinEnter * match ExtraWhitespace /\s\+$/
autocmd InsertEnter * match ExtraWhitespace /\s\+\%#\@

and I 'auto-strip' it from files when saving them, in my case *.rb for ruby files, again in my ~/.vimrc

function! TrimWhiteSpace()
    %s/\s\+$//e
endfunction
autocmd BufWritePre     *.rb :call TrimWhiteSpace()