strangely silent compiler

[Orfeo]

I've:
```
module anomalo.util;

// Foo doesn't exist  anywhere!!!!!

Foo toJsJson(string type, Args...)(string id, Args args) {
    static if (type == "int" || type == "outcome") {
       return Json(["id" : Json(id), "type" : Json(type), "value" 
: Json(0),]);
    } else {
       static assert(0, "invalid type");
    }
}

```

So:
```
$ dub build
```
No error!

```
$ /usr/bin/dmd -lib -ofliba.a -debug -g -w -I. src/anomalo/util.d 
-vcolumns
```

No error!

Here [github](https://github.com/o3o/anomalo) my project.

Thank you