Hi Vidhya,
Val is final i mean once its initialized it cannot be changed.
whereas Var can be changed when you operate or perform calculations on it.
*In Scala Interpreter *
scala> val a=10;
a: Int = 10
scala> a=20;
<console>:5: error: reassignment to val
a=20;
^
scala> var s=40;
s: Int = 40
scala> s=20;
s: Int = 20
scala> a=a+1
<console>:5: error: reassignment to val
a=a+1
^
scala> s=s+1
s: Int = 21
*The reason for this can be known when you write an object like
*object SMS{
val a=10;
var b =20;
}
After compiling it run this command
javap -private SMS$
Compiled from "SMS.scala"
public final class SMS$ extends java.lang.Object implements
scala.ScalaObject{
public static final SMS$ MODULE$;
private int b;
private final int a;
public static {};
public SMS$();
public void b_$eq(int);
public int b();
public int a();
public int $tag() throws java.rmi.RemoteException;
}
you will observe a is final hence cannot be changed.Also
void b_$eq(int)
function is related to var b which signifies that var b is now Int as its
initialized with 20 (an int).
Now try initializing b with 20.0 then the function will be
public void b_$eq(double);
I hope this helps.
Thanks,
SMS.
On Mon, Jun 22, 2009 at 12:41 PM, Vidhya Ranganathan
<[email protected]>wrote:
>
>
> Hi all,
> Can somebody explain the difference between, Var and Val in Scala?
>
> Regards,
> Vidhya
>
>
[Non-text portions of this message have been removed]
