as far as
Also, so far as. To the extent, degree, or amount that. This phrase alone is always used to modify a verb, as in As far as I can tell it's an authentic antique, or It's a good job as far as it goes, but it may need more work, or James said that, so far as he can remember, he's never met Mike. [c. 1300] Also see the subsequent idioms beginning with as far as.