A program in Refal Plus may consist of several modules, one of which must export the
function Main. The execution of the program amounts to evaluating the call to
the function Main.
The function
Main is said to be the main function of the program, and must
have the following declaration:
$func Main = e;
If a function with the name Main is declared in some other way, but,
nevertheless, is exported by a module, this situation is considered to be an error.
The execution of the Refal program amounts to evaluating the call to the function
Main, the argument of the call being empty:
<Main >
The module that contains the definition of the main function is permitted to have no
interface part, in which case the Refal Plus compiler assumes the module's interface to
consist of the single function declaration:
$func Main = e;