Method tfp

chapter18/src/test/java/com/seaofnodes/simple/Eval2.java:295–295

(Node n)

    static double d( Node n ) { Object d = F.get(n); return d==null ? 0 : (Double)F.get(n);  }
    // Fetch and unbox a function constant
    static TypeFunPtr tfp(Node n) { return (TypeFunPtr)F.get(n); }
    // Fetch and unbox a closure
    static Closure clj(Node n) { return (Closure)F.get(n); }