phantom-type

A PhantomData analog which prevents "parameter is never used" error, but does not produce any restrictions in contrast with PhantomData.

Optional no_std

If your crate has std feature, use the following method to specify phantom-type dependency:

[features]
default = ["std"]
std = ["phantom-type/std"]

[dependencies]
phantom-type = { version = "*", default-features = false }