rustc warns of unused imports

[mcandre]

When I construct a regex in a lazy_static, then rustc often presents a spurious warning that the regex import is unused.

I tried moving use regex::Regex; into lazy_static, but that actually makes the compilation hard fail.

I also added a unit test with #[test], but that still triggers the spurious unused import warning.

What are we supposed to do to resolve that?

For context, this problem happens when using lazy_static members inside of a PEG grammar.

(I know, weird to import the regex library into a PEG grammar. But I have my reasons.)

[BurntSushi]

Can you provide an example that others can reproduce please?