inoremap <silent><expr> <cr> pumvisible() ? coc#_select_confirm() : "\<C-g>u\<CR>\<c-r>=coc#on_enter()\<CR>"

" use <tab> for trigger completion and navigate to the next complete item
function! s:check_back_space() abort
  let col = col('.') - 1
  return !col || getline('.')[col - 1]  =~ '\s'
endfunction

inoremap <silent><expr> <Tab>
      \ pumvisible() ? "\<C-n>" :
      \ <SID>check_back_space() ? "\<Tab>" :
      \ coc#refresh()