I'm making a toy numerical crate, and some of my return types are complex numbers. I'm relying on num-complex under the hood, but my return types are also complex numbers. I considered simply returning tuples of f64 values, but that doesn't feel right.
If you were using a crate, how would you want to see this done? I hate to force anyone to include a dependency they don't want—even one as well-maintained as num-complex. Is it alright to pub use the complex type, or is there a more acceptable way?
Thanks for your time!
pub use num_complex::Complex64;
// and return a Complex64 value...
or
use num_complex::Complex64;
// and return a tuple of `f64`?
This is called a "public dependency".
The proper way to handle this will be, in the future when RFC 3516 is stabilized, to mark the dependency as public = true in Cargo.toml.
In the meantime (and maybe after that too), you can (and should) re-export that dependency from your library:
pub extern crate num_complex;
Then, users can refer to it as your_library::num_complex.