Cargo Features

Permutations has no features set by default.

[dependencies]
permutations = { version = "0.1.1", features = ["random"] }
random = rand

Enable the generation of random points in a bounding box.

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.

rand random?