Professional IronPython

8.
Type 
Calcs.VB
for the new filename and press Enter. Visual Studio displays a dialog box that 
asks whether you’d like to rename all of the 
Class1.vb
references to match the new filename.
9.
Click Yes. The project is ready for use.
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CHAPTER 17
ExtEnding ironPython Using VisUal Basic.nEt
Renaming the class file also renames any hidden elements. For example, the 
namespace for this project is hidden, but it’s renamed to 
Calcs
. It’s impor-
tant to keep the renaming of hidden elements in mind as you work with the 
IronPython code.
developing the Visual Basic.NET Extension
The Visual Basic.NET extension code for this example is relatively simple. Listing 17-1 shows the 
constructor, operator overrides, and methods used for this example.
LISTINg 17-1: 
 A simple calculations extension
Public Class Calcs
Private Data As Int32
Public Sub New(ByVal Value As Int32)
Me.Data = Value
End Sub
Public Overrides Function ToString() As String
Return Data.ToString()
End Function
Public Shared Operator +(ByVal Value1 As Calcs, _
ByVal Value2 As Calcs) As Calcs
Return New Calcs(Value1.Data + Value2.Data)
End Operator
Public Shared Operator -(ByVal Value1 As Calcs, _
ByVal Value2 As Calcs) As Calcs
Return New Calcs(Value1.Data - Value2.Data)
End Operator
Public Shared Operator *(ByVal Value1 As Calcs, _
ByVal Value2 As Calcs) As Calcs
Return New Calcs(Value1.Data * Value2.Data)
End Operator
Public Shared Operator /(ByVal Value1 As Calcs, _
ByVal Value2 As Calcs) As Calcs
Return New Calcs(Value1.Data / Value2.Data)
End Operator
Public Function Inc() As Calcs
Return New Calcs(Me.Data + 1)
End Function
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