Note that lexing and parsing is extremely quick, and I wouldn't focus on trying to trim this out, you won't get much performance out of that.-Steve
For the record, a D file containing only `import std;` type checks via
```sh time dmd import_std.d -o- ``` in 0.20s whereas ```sh time dmd import_std.d -o- ``` in 0.45s on my ThreadRipper.
