ChalkExpressionNode

One node of a compiled expression tree. The arithmetic kinds are computed by evaluateChalkExpressionNode; everything else — a condition (D56), a typed value, a list, a map, an application -> (D69), any operator over a list (D72) — by the compiler's evaluate, through evaluateChalkValue. One op node for every operator, a named one (round, sqrt) included (D70).