A student in my class recently asked how to do enums in X10.
Here is a simple illustration, using structs.
Best,
Vijay
Go, Pluto!
package examples;
/**
* An illustration of how to do enum's in X10.
* Implement an enum as a struct with private fields. It may have as
many methods
* as you want.
*
* <p>Make the constructors private. Have public static fields for all
the desired
* values of the enum type. Have a static field (e.g. Planets below) that
* contains an Iterator over the array of all the fields.
*
* <p>Define an equals method if you wish equality to reflect equality
on a subset
* of the fields. Otherwise the default equality should suffice.
*
*/
public struct Planet {
private val mass:Double;
private val radius:Double;
private val name:String;
private def this(m:Double, r:Double,n:String) {
this.mass=m;
this.radius=r;
this.name=n;
}
public static val G:Double=6.67e-11;
public def mass():Double=mass;
public def radius():Double=radius;
public def name():String=name;
public def gOnSurface():Double= G*mass/(radius*radius);
public def weightOnSurface(m:Double):Double=m*gOnSurface();
public def toString()=name;
public static def toPlanet(s:String):Planet {
for (p in Planets)
if (s.equalsIgnoreCase(p.name()))
return p;
throw new RuntimeException("No such planet.");
}
public static val MERCURY=Planet(3.303e23,2.4937e6,"Mercury");
public static val VENUS=Planet(4.869e24,6.0518e6,"Venus");
public static val EARTH=Planet(5.976e24,6.37184e6,"Earth");
public static val MARS=Planet(6.421e23,3.3972e6,"Mars");
public static val JUPITER=Planet(1.9e27,7.1492e7,"Jupiter");
public static val SATURN=Planet(5.688e26,6.0268e7,"Saturn");
public static val URANUS=Planet(8.686e25,2.5559e7,"Uranus");
public static val NEPTUNE=Planet(1.024e26,2.4746e7,"Neptune");
public static val PLUTO=Planet(1.27e22,2.274e7,"Pluto");
public static val Planets=[MERCURY,VENUS,EARTH,MARS,JUPITER,SATURN,
URANUS,NEPTUNE,PLUTO].values();
public static def main(args:Array[String](0)) {
if (args.size !=2) {
Console.OUT.println("Usage: <weight:Double> <name:String>");
return;
}
val w = Int.parseInt(args(0));
val q = toPlanet(args(1));
for (p in Planets) {
if (q !=p)
Console.OUT.printf("You weigh %s kg on %s.%n",
[p.weightOnSurface(w),p]);
}
}
}
------------------------------------------------------------------------------
All the data continuously generated in your IT infrastructure
contains a definitive record of customers, application performance,
security threats, fraudulent activity, and more. Splunk takes this
data and makes sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-novd2d
_______________________________________________
X10-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/x10-users
