version(Main) like python's __name__ == "__main__"

[Lionello Lunesu]

I'd like to suggest a new predefined version identifier called "Main" 
which is defined on the main module only. The definition of "main 
module" would be:

* the first module on the command line, or
* the module whose name will be used for the executable, or
* the module mentioned after DMD's "-run"

The two issues with this suggestion are:

* vagueness of the definition of "main module"
* Main version identifier is set for one module only (by definition)

It's use would be similar to Python's "__main__" [1]:

version(Main)
{
void main()
{
   // test code
}
}

It would allow one to write small examples/tests in each module, that 
can be executed immediately, but won't cause conflicts when linked 
against in a larger project.

L.

[1] http://docs.python.org/lib/module-main.html