This is intended as a cleaned up version of #2698 & #2552, which partially addresses the issue in #2550.
The issue had two components:
This pull request addresses only the first of these two issues. I feel that the issues are sufficiently different to deserve separate consideration (and separate pull requests). In particular, %Rpull currently requires variable names to be separated by spaces as well and I think we should ensure that the semantics for %Rpush and %Rpull remain identical.
I'm going to close #2698 and link to this issue.
Fix issue #2550
added tests for new feature
Test results for commit 5e268bb merged into master (ca39815)
Not available for testing: python2.6
Looks good to me.