lint() output should be class c("lints", "list") for S3 dispatch

[MichaelChirico]

I am working on something where I need to edit the line numbers of the lint() output; a natural way to do that is like so:

l <- lint(...)
l <- lapply(l, within, line_number <- line_number + 1)

But this fails because within attempts to dispatch on lints class. For now, we need to call the method explicitly:

l <- lapply(l, within.list, line_number <- line_number + 1)

We could also define a within.lints() method, but that only works for this specific case, I think the problem is more general (it will affect other generics used too process the lint() output, too).

[AshesITR]

Ditto for Lint(), right?