support controlling whether bufferline variables get overwritten. resolves #195.

autoload/airline/extensions/bufferline.vim

@@ -1,14 +1,18 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
 " vim: et ts=2 sts=2 sw=2
 
+let s:overwrite = get(g:, 'airline#extensions#bufferline#overwrite_variables', 1)
+
 function! airline#extensions#bufferline#init(ext)
-  highlight bufferline_selected gui=bold cterm=bold term=bold
+  if s:overwrite
-  highlight link bufferline_selected_inactive airline_c_inactive
+    highlight bufferline_selected gui=bold cterm=bold term=bold
-  let g:bufferline_inactive_highlight = 'airline_c'
+    highlight link bufferline_selected_inactive airline_c_inactive
-  let g:bufferline_active_highlight = 'bufferline_selected'
+    let g:bufferline_inactive_highlight = 'airline_c'
-  let g:bufferline_active_buffer_left = ''
+    let g:bufferline_active_highlight = 'bufferline_selected'
-  let g:bufferline_active_buffer_right = ''
+    let g:bufferline_active_buffer_left = ''
-  let g:bufferline_separator = ' '
+    let g:bufferline_active_buffer_right = ''
+    let g:bufferline_separator = ' '
+  endif
 
   let g:airline_parts.file = '%{bufferline#refresh_status()}'.bufferline#get_status_string()
 endfunction

doc/airline.txt

@@ -200,6 +200,15 @@ configuration values that you can use.
       \ 'y': 88,
       \ 'z': 45,
       \ })
+<
+                                                        *airline-bufferline*
+vim-bufferline <https://github.com/bling/vim-bufferline>
+
+* enable/disable bufferline integration >
+  let g:airline#extensions#bufferline#enabled = 1
+<
+* determine whether bufferline will overwrite customization variables >
+  let g:airline#extensions#bufferline#overwrite_variables = 1
 <
                                                             *airline-branch*
 fugitive.vim <https://github.com/tpope/vim-fugitive>