avoid TOPLEVEL_BINDING pollution
avoid TOPLEVEL_BINDING pollution

Evaluating user inputs in the TOPLEVEL_BINDING can pollute global
toplevel local variable namespace because there is only one
TOPLEVEL_BINDING across the entire process.  Here in this method
we do not need such thing.  Duplicating that binding to create
dedicated one for this purpose should effectively kill such global
side effects.

mvz/bundler,bundler/bundler,dilumnavanjana/bundler,mvz/bundler,bundler/bundler,dilumnavanjana/bundler