yihui/knitr — pull request #664 by klmr (2013-11-14 10:52:33+00:00)
Title: Make knit “vanilla”

Currently knit loads custom .Rprofile environment files. This is
probably not what you normally want from it – if nothing else it makes
it harder to reproduce (= recompile on another system) the document.

This pull request adds the `--vanilla` flag to change this.