.vimrc

function! MyCR()
 echom 'MyCR()'
 " XPTinfo() returns a list if snippet is active.
 if type(XPTinfo()) == type([])
   echom 1
   XPTcrash
   return ''
 elseif pumvisible()
   echom 2
   return "\<C-Y>"
 elseif delimitMate#WithinEmptyPair()
   echom 3
   return "\<C-R>=delimitMate#ExpandReturn()\<CR>"
 else
   echom 4
   return "\<C-G>u\<CR>"
 endif
endfunction

inoremap <expr> <CR> MyCR()