I'm using lots of vim plugins like nerdtree, fugitive etc.
recently I was adding some new mappings and some of the plugins broke
I traced it down to the following line
cmap E e
WTF? :) why would it break NerdTree?
UPDATE: forgot to mantion how it breaks ;). I get the following error:
E492: Not an editor command: :NeRDTreeToggle
UPDATE2: Duh! I now know what happens. mapping E to e turns NERDTreeToggle into NeRDTreeToggle so the new question is how to map E to e properly? i.e. so that ":E foo.txt" will do the same as ":e foo.txt"