|savemap| is the library to provide a way
to restore current mapping(s)/abbreviation(s) "perfectly".

...But remember, you can always use |:map-<buffer>| for "simple" case.

>
    nmap foo blahblahblah

    let foo_nmap = savemap#save_map('n', 'foo')
    if empty(foo_nmap)
        echoerr 'your vim version is lower than 7.3.032!'
    endif

    nmap foo bar
    " Execute 'bar'.
    normal foo

    call foo_nmap.restore()
    " Execute 'blahblahblah'.
    normal foo


Omit 2nd arg of |savemap#save_map()| to save all mappings of the mode.
>
    let normal_mappings = savemap#save_map('n')
    if empty(normal_mappings)
        echoerr 'your vim version is lower than 7.3.032!'
    endif

   " Clear!
    nmapclear

    " Map own mappings.
    nnoremap a b
    nnoremap c d
    ...

    try
        ... " Do it
    finally
        call normal_mappings.restore()
    endtry


See doc/savemap.txt or :help savemap for more details.