strip white spaces
Just Read It! R will open the file() connection automatically
gist is not required when there are 3 arguments
you do not need to clean up temp files; R will do that on exit
source code can be .r as well
vectorize the code to report all offending lines at once
it seems the destination filename does not matter
code width > 65 does not seem to be *that* horrible; how about just a warning?

on my screen, width = 80 seems to work pretty well (no wrapping yet)

the convention is width <= 80, so using 65 may be inconvenient since we have to adjust the preference in our text editor