> For Compatibility with no_std tgts, e.g. embedded, Use the no_std feature.

Note, this is not the recommended way to use Rust feature flags. They are additive and so the correct way to make a `no_std` compatible crate is to have a `std` feature flag that conditionally enables use of the `std` library.

Referring to Effective Rust:

> Note that there's a trap for the unwary here: don't have a no_std feature that disables functionality requiring std (or a no_alloc feature similarly). As explained in Item 26, features need to be additive, and there's no way to combine two users of the crate where one configures no_std and one doesn't—the former will trigger the removal of code that the latter relies on. - https://www.lurklurk.org/effective-rust/no-std.html