Some notes about Implicitly typed variables

During some C# LINQ  project i have discovered some limitations and some things that can be done when working with the var new syntax,Here is a brief summery:

1. When declaring a variable , you must assign its value on the declaration line.

   //Implicitly-typed local variables must be initialized
   var someVariable;

2. Again:  must be done exactly when declaring

   //Implicitly-typed local variables must be initialized
   var someVariable;
   someVariable = 1;

3. Cannot assign null as an Initial value

//Cannot assign <null> to an implicitly-typed local variable
 var oObj = null;

  4. However, after initialized can be null.

var oObj = new Object();
oObj = null;

  5. It is permitted to return a var value as long as the function is typed, such as:

     private int GetNumber()
     {
       var x = 5;
       return x;
     }

    6. Another limitation is , you cannot define a class member as var!!!