[Rd] Method dispatch for function

[Stavros Macrakis]

(I had sent this to r-help and got no responses -- perhaps r-devel is
a better list for this question?)

How can I determine what S3 method will be called for a particular
first-argument class?

I was imagining something like functionDispatch('str','numeric') =>
utils:::str.default , but I can't find anything like this.

For that matter, I was wondering if anyone had written a version of
`methods` which gave their fully qualified names if they were not
visible, e.g.

methods('str') =>
    utils:::str.data.frame    utils:::str.default
stats:::str.dendrogram    stats:::str.logLik    utils:::str.POSIXt

or

methods('str') =>
     $utils
           "str.data.frame" "str.default"    "str.POSIXt"
     $stats
           "str.dendrogram" "str.logLik"

Thank you,

             -s