mixin D code into D code

[Walter Bright]

Pragma wrote:
> Take something like DSP: you have an embedded D compiler that is invoked 
> in response to a change in a web-script written in D. Without being able 
> to specify where these literal imports are coming from, the results 
> could be disastrous.
> 
> There should be an option to disable the behavior, and the path 
> searching behavior of the import expression needs to be well defined.  
> Ideally, this would involve a separate switch for specifying import 
> paths as distinct from the module include path (so it can be routed to 
> /dev/null if need be). The last thing we want is people hijacking a 
> server, just because a compiler was provided under httpd's process (with 
> it's permissions).

I think you're right.