Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      uCalc.DefaultInstance.DefineVariable("instance = 'original default'")
      
      Dim ucB As New uCalc()
      Dim ucC As New uCalc()
      Dim ucD As New uCalc()
      
      ucB.Eval("instance = 'B derived from -> ' + instance")
      ucC.Eval("instance = 'C derived from -> ' + instance")
      ucD.Eval("instance = 'D derived from -> ' + instance")
      
      ucC.IsDefault = true
      
      Dim ucE As New uCalc()
      ucE.Eval("instance = 'E derived from -> ' + instance")
      
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("'Default: ' + instance"))
      
      Console.WriteLine(uc.EvalStr("instance")) '// Note: this is not, nor was the default
      Console.WriteLine(ucB.EvalStr("instance"))
      Console.WriteLine(ucC.EvalStr("instance"))
      Console.WriteLine(ucD.EvalStr("instance"))
      Console.WriteLine(ucE.EvalStr("instance"))
      
      '// Note: Unlike this example, it is generally best to always
      '// create a new instance first and then set it as default
   End Sub
End Module

Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      uCalc.DefaultInstance.DefineVariable("val = 'original default'")
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("val"))
      
      uc.DefineVariable("val = 'uc'")
      uc.IsDefault = true
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("val"))
      
      Dim ucB As New uCalc()
      ucB.DefineVariable("val = 'ucB'")
      ucB.IsDefault = true
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("val"))
      
      Dim ucC As New uCalc()
      ucC.DefineVariable("val = 'ucC'")
      ucC.IsDefault = true
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("val"))
      
      uCalc.DefaultClear()
      
      '// The original unnamed default instance is reset so user variable val no longer exists
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("val"))
      
      '// The other instances are removed from Default list but remain active
      Console.WriteLine(uc.EvalStr("val"))
      Console.WriteLine(ucB.EvalStr("val"))
      Console.WriteLine(ucC.EvalStr("val"))
   End Sub
End Module

Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      
      '// In C# and VB you should use "using".
      '// In C++ you can flag a uCalc object for
      '// auto-release with Owned(), or by setting
      '// the last parameter of the constructor to true.
      
      uc.IsDefault = true '// Set uc as the default uCalc object
      uCalc.DefaultInstance.DefineVariable("Value = 'Original uc object'")
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("Value")) '// Outputs: Original uc object
      
      '// Use "using" so that the object is auto-released when it it goes out of scope
      Using uCalcTemp As New uCalc()
         uCalcTemp.IsDefault = true '// Set uCalcTemp as the default uCalc object
         uCalc.DefaultInstance.DefineVariable("Value = 'uCalcTemp object'")
         Console.WriteLine(uCalc.DefaultInstance.EvalStr("Value")) '// uCalcTemp object
      End Using
      '// uCalcTemp goes out of scope here, and the default uCalc object reverts back to uc
      
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("Value")) '// Original uc object
      
      If True Then
         Dim uCalcSticky As New uCalc() '// remains the default even after going out of scope
         uCalcSticky.IsDefault = true '// Set uCalcSticky as the default uCalc object
         uCalc.DefaultInstance.DefineVariable("Value = 'uCalcSticky object'")
         Console.WriteLine(uCalc.DefaultInstance.EvalStr("Value")) '// Outputs: uCalcSticky object
      End If    '// The uCalcSticky object itself goes out of scope here, but internally it remains the default uCalc object
      
      Console.WriteLine(uCalc.DefaultInstance.EvalStr("Value"))
   End Sub
End Module

Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      '// Original default instance
      uCalc.DefaultInstance.DefineVariable("id = 'Original'")
      Console.WriteLine($"Current Default ID: {uCalc.DefaultInstance.EvalStr("id")}")
      
      '// Push a new default instance onto the stack
      Dim ucA As New uCalc()
      ucA.DefineVariable("id = 'Instance A'")
      ucA.IsDefault = true
      Console.WriteLine($"Current Default ID: {uCalc.DefaultInstance.EvalStr("id")}")
      
      '// The 'NewUsing' block creates a temporary, scoped default instance
      
      '// The following instance will be auto-released at the end of the block
      Using ucB As New uCalc()
         ucB.DefineVariable("id = 'Instance B (temp)'")
         ucB.IsDefault = true '// Pushes 'ucB' onto the stack
         Console.WriteLine($"Current Default ID: {uCalc.DefaultInstance.EvalStr("id")}")
      End Using
      
      '// 'ucB' has gone out of scope, so the default reverts to the previous one ('ucA')
      Console.WriteLine($"Current Default ID (after scope exit): {uCalc.DefaultInstance.EvalStr("id")}")
      
      '// Manually unset 'ucA'
      ucA.IsDefault = false
      Console.WriteLine($"Current Default ID (after unset): {uCalc.DefaultInstance.EvalStr("id")}")
   End Sub
End Module

Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      '// --- Main Application Context ---
      '// Starting with the 'uc' object as the initial default.
      uCalc.DefaultInstance.DefineConstant("PI = 3.14159")
      Console.WriteLine($"Initial Count: {uCalc.DefaultCount}")
      
      '// --- A Plugin needs a temporary, isolated context ---
      Using moduleCalc As New uCalc()
         moduleCalc.IsDefault = true '// Push the new instance onto the stack.
         Console.WriteLine($"Count after module pushes new default: {uCalc.DefaultCount}")
         
         '// The module's context is now active.
         '// uCalc::DefaultInstance() would now return 'moduleCalc'.
      End Using
      
      '// When 'moduleCalc' goes out of scope, it's destroyed and automatically
      '// removed from the stack, restoring the previous default.
      
      Console.WriteLine($"Count after module instance is disposed: {uCalc.DefaultCount}")
      
      '// Verify the original default instance is active again.
      Dim result = uCalc.DefaultInstance.EvalStr("PI")
      Console.WriteLine($"Original context restored. PI = {result}")
   End Sub
End Module