zsh 5.3.1 (x86_64-pc-linux-gnu)

When switching between prompt theme walters and some
other themes I noticed that the right prompt remained. On
checking I found walters was the only theme that used
RPROMPT to set the right prompt. The only other theme
to set the right prompt is bart, but it used RPS1.

After switching from walters to say adam, I unset "RPS1",
but the right prompt remained.  I then typed
"unset RPROMPT" and the right prompt was no longer there.

The output of a script I wrote doesn't match what I though it
should, but then again it was just strange.

Current state of RPROMPT and RPS1
    RPROMPT:
    RPS1:
Set RPROMPT to RPROMPT
    RPROMPT:  RPROMPT
    RPS1:
Set RPS1 to RPS1
    RPROMPT:  RPS1
    RPS1:  RPS1
Unset RPRMOPT
    RPROMPT:
    RPS1:
Unset RPS1
    RPROMPT:
    RPS1:
Set RPROMPT to RPROMPT
Set RPS1 to RPS1
    RPROMPT:  RPS1
    RPS1:  RPS1
Unset RPS1
    RPROMPT:
    RPS1:
Unset RPRMOPT
    RPROMPT:
    RPS1:

Strange!  The results here contradict what I was seeing
with the right prompt and unset RPS1. I'm also attaching
the script.

Thanks for zsh and your help.

Jim