[R] Identify Objects that end with .f (and all caps)

[Sparks, John James]

Dear R Helpers,

I am trying to find a way to identify all the objects in my environment
that are all caps and then end with .f.  I can do the all caps part pretty
easily, but I have tried a number of variations on the \ and can't get a
recognition of that operator.  As a simple example

A.f<-"foo1"
AA.f<-"foo2"
aa.f<-"foo3"
A.a<-"foo4"
ls()
[1] "A.a"  "A.f"  "aa.f" "AA.f"
temp1<-ls(pattern="[A-Z]")
temp1
[1] "A.a"  "A.f"  "AA.f"
> temp2<-ls(pattern=\f)
Error: unexpected input in "temp2<-ls(pattern=\"

The end goal is to isolate A.f and AA.f and not the others.
In terms of just getting the 'ending with .f' portion, I have tried a
number of variations in the pattern=\f, but can't get R to recognize what
I want.

Your guidance would be much appreciated.
--John J. Sparks, Ph.D.