Example : So far he hasn't called.
The sun isn't up yet.

Synonyms : as yet, heretofore, hitherto, thus far, til now, until now, up to now, yet

Example : Insofar as it can be ascertained, the horse lung is comparable to that of man.
So far as it is reasonably practical he should practice restraint.

Synonyms : in so far, insofar, to that degree, to that extent

Example : This is the best so far.
The largest drug bust yet.

Synonyms : yet