rstudio/rmarkdown — pull request #137 by yihui (2014-06-23 22:10:39+00:00)
Title: vectorize pandoc_path_arg(), not assuming path is a scalar

this fixes the warning under Windows reported by http://rmarkdown.rstudio.com/#comment-1447899447

I'm not entirely sure if you expect `pandoc_path_arg()` to accept scalars only. If that is the case, I guess we have a deeper problem, because `path` here can be a vector of length > 1.