It forks from a.vim, but fix bug when the files in pairs in different folder.
It can works well even the folds at far different level when config with a var named 'g:selfConfigPartPath'.
eg set this in your vim config file:
let g:selfConfigPartPath='export:h:src' 
The 'export','src' etc. is the last level folder of the file.

A few of quick commands to swtich between source files and header files quickly.

:A switches to the header file corresponding to the current file being edited (or vise versa)
:AS splits and switches
:AV vertical splits and switches
:AT new tab and switches
:AN cycles through matches
:IH switches to file under cursor
:IHS splits and switches
:IHV vertical splits and switches
:IHT new tab and switches
:IHN cycles through matches
<Leader>ih switches to file under cursor
<Leader>is switches to the alternate file of file under cursor (e.g. on  <foo.h> switches to foo.cpp)
<Leader>ihn cycles through matches

E.g. if you are editing foo.c and need to edit foo.h simply execute :A and you will be editting foo.h, to switch back to foo.c execute :A again. 

Can be configured to support a variety of languages. Builtin support for C, C++ and ADA95