Binaryworld - CStack - a class module for implementing Last-In-First-Out (stack) str ... [ VB -> Class & object ]

'--------------------------------------------------
'
' The CSTACK class
'
' Usage:
'  Dim st As New CStack
'
'  ' push two values on the stack
'  st.Push 1234
'  st.Push 4567
'  ' display number of elements in the stack
'  Debug.Print "Count = " & st.Count
'  ' peek at the element on top of stack
'  Debug.Print "Peek = " & st.Peek
'  ' print the elements on the stack while popping them
'  Do While st.Count
'    Debug.Print "TOS item = " & st.Pop
'  Loop
'
'---------------------------------------------------

' this is the collection that holds the values
Dim colValues As New Collection

' add a new value onto the stack
Sub Push(value As Variant)
  colValues.Add value
End Sub

' Pop a value off the stack - raise error if stack is emtpy
Function Pop() As Variant
  Pop = colValues.Item(colValues.Count)
  colValues.Remove colValues.Count
End Function

' Return the value on top of the stack, without popping it
' raise error if stack is empty
Function Peek() As Variant
  Peek = colValues.Item(colValues.Count)
End Function

' Return the number of values in the stack
Function Count() As Long
  Count = colValues.Count
End Function