Cargo Features

[dependencies]
fmt-interspersed = { version = "0.5.0", default-features = false, features = ["std", "alloc"] }
default = std

The std feature is set by default whenever fmt-interspersed is added without default-features = false somewhere in the dependency tree.

std default = alloc
alloc std

fmt-interspersed has 3 features without comments.