call :tohex 14 result
rem More code...
:tohex <innum> <outvar>
set dec=%1
set outvar=%~2
rem %n and %~n are functionally identical, but %~n is slightly safer.
goto :eof
This takes the additional parameters from the call
as if the function was a separate Batch file.
Note: the <parameter>
isn't necessary, but it helps with readability.