A module internal to Incremental. Users should see Incremental_intf.
A Reduce_balanced.t is a kind of DAG node. 'a is the type of value being folded.
val create : Incremental_kernel__.State.t ‑> 'a Incremental_kernel__.Node.t array ‑> f:('a ‑> 'b) ‑> reduce:('b ‑> 'b ‑> 'b) ‑> 'b Incremental_kernel__.Node.t option