Inherent method wrappers around traits

[ExpHP]

I often feel like it is a design mistake when it is necessary to import a trait in order to use methods of a type (defined in the same crate) that seem like they should be inherent. Or perhaps, when it seems reasonable that people would want to use the method in non-generic contexts.

In this case, one can internally use a macro to generate inherent methods for each type that wraps the methods. (note: I looked around and haven't explicitly found an example of this yet; maybe this is just my own pet solution)

I'm not sure on the precise guidelines, but I believe some possible signs that a trait's impls should be wrapped with inherent methods are:

• when it is not expected that types outside the crate will frequently need to implement the trait
• if one of the reasons for creating the trait is to "make the implementation easier"

(actually, these are all signs that a trait should not be public in the first place; but perhaps it is exposed for the sake of a free function)

Without a clear guideline, I think what this really needs at this point is just discussion.

[ExpHP]

I was probably going to wait to find examples before posting this but unfortunately I fat-fingered the "Post" button. Anyways, I'm done fixing it up, so perhaps others can share their thoughts on whether such a guideline is needed.