set complete+=b " scan other loaded buffers that are in the buffer list
set complete+=u " scan the unloaded buffers that are in the buffer list
set complete+=t " scan tags
+set complete+=i " scan current and included files
+set complete+=kspell " use the currently active spell checking |spell|
" whether to use a popup menu for Insert mode completion
set completeopt=longest,menuone,preview
set diffopt+=filler " show filler lines
set diffopt+=vertical " always vertical split
set diffopt+=iwhite " ignore white space
+set diffopt+=context:10 " 10 lines context between changes
" reading and writing files {{{2
set modeline " read modelines