I don't think it is. Angular is very much tied to states. In fact, if you watch a continuous function, you'll hit infinite recursion as the state is always dirty.
To make continuous functions work in the browser, the digest cycle needs to stop even when the state is dirty. Angular doesn't stop until the state is no longer dirty.
EDIT
Dart can be used for FRP though: http://victorsavkin.com/post/55007674849/functional-reactive-programming-in-dart