Module Name Resolution

[Jason C. Wells via Digitalmars-d-learn]

Suddenly it occurs to me that the module namespace and the 
filesystem namespace do not necessarily have a one for one match, 
even though they do by default. When one specifies all the D 
source files on the command line, any differences between the 
module namespace and the filesystem namespace are handled 
automagically by dmd. The "module" declaration is the code by 
which the module namespace is manually defined.

Hence the repeated advice to supply all the filenames on the 
command line.