2 Checks for methods that should live in a trait
3 implementation of a `std` trait (see [llogiq's blog
4 post](http://llogiq.github.io/2015/07/30/traits.html) for further
5 information) instead of an inherent implementation.
8 Implementing the traits improve ergonomics for users of
9 the code, often with very little cost. Also people seeing a `mul(...)`
11 may expect `*` to work equally, so you should have good reason to disappoint
18 fn add(&self, other: &X) -> X {