Question

I try create a map for open ~/.vimrc, but open the ~/.vimrc only when the buffer is empty, else split and open.
I try this

fun! BufferIsEmpty() "{{{                                                                
    if line('$') == 1 && getline(1) == ''                                                
        return 1                                                                         
    else                                                                                 
        return 0                                                                         
    endif                                                                                
endf "}}}                                                                                
fun! NotEmptySplit() "{{{                                                                
    if !BufferIsEmpty()                                                                  
        sp                                                                               
    endif                                                                                
    return                                                                               
endf                                                                                     
command! -nargs=0 NotEmptySplit call NotEmptySplit()  
nnoremap <silent><leader>ve :NotEmptySplit <bar> ~/.vimrc<CR>

but I get this error

E488: Trailing characters

Answer 1

To take kev’s excellent answer a bit further:

How about pulling out a generic ‘open file in split if buffer not empty’ function.

fu! OpenInSplitIfBufferDirty(file)
    if line('$') == 1 && getline(1) == ''
        exec 'e' a:file
    else
        exec 'sp' a:file
    endif
endfu

nnoremap <silent> <leader>ve :call OpenInSplitIfBufferDirty($MYVIMRC)<cr>
command -nargs=1 -complete=file -bar CleverOpen :call OpenInSplitIfBufferDirty(<q-args>)