`clippy::type_complexity`

Name the nested type with a type alias or a dedicated struct so signatures say what they carry.

What it reads

Clippy, with the compiler behind it. The only pass that compiles.

Lowest tier: real, and rarely urgent.

The tier bounds how severe a rule may be; its category bounds the tier.

Turn it off, or make it blocking, without touching the code it flags:

rust-doctor --rule clippy::type_complexity=off .
rust-doctor --rule clippy::type_complexity=error .