Incremental parsing is designed for just this use case. The last major work in the area that I know of is Tim Wagner's PhD thesis http://www.cs.berkeley.edu/Res

Incremental parsing is designed for just this use case. The last major work in the area that I know of is Tim Wagner's PhD thesis http://www.cs.berkeley.edu/Research/Projects/harmonia/papers/twagner-thesis.pdf http://www.cs.berkeley.edu/Research/Projects/harmonia/papers...