Module without object file?

[Steven Schveighoffer]

On 1/6/22 6:06 PM, kdevel wrote:
>> When you import this file, the compiler sees that it has imports, and 
>> assumes you must have built the `ModuleInfo` in some object somewhere, 
>> so it outputs a reference for the import graph.
> 
> Makes sense. It seems that if there are just type definitions with enum 
> constants the module is a "leaf module". As soon as I add the delegate 
> which calls writefln
> 
> ```somemodule.d
> struct File {
>     enum title = "File";
>     enum void function (string) foo = (a => writefln ("a <%s>", a));
> }
> ```
> 
> to the source the linker complains about the missing ModuleInfo.

The reasons the compiler decides to require `ModuleInfo` are somewhat 
unspecified. I would have expected just importing std.stdio would do it, 
but maybe you have to actually use something from that module.

-Steve