Cargo Features

[dependencies]
graph-traits = { version = "0.1.1", default-features = false, features = ["petgraph"] }
default = petgraph

The petgraph feature is set by default whenever graph-traits is added without default-features = false somewhere in the dependency tree.

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.

petgraph default

Enables petgraph ^0.5.1