[plt-scheme] Anyone competent in VB? MzCom & Excel question.

Martial Tarizzo wrote:
> The problem is not in MzCom, but in your code. See below.

Thank you for your proposed solution. However I am incompetent in VB and 
your explanation pre-supposes I have much knowledge about VB and 
presents a solution possibly generated by a VB analysis tool of which I 
know nothing.

Could you please either make your solution web accessible in an ".xls" 
spreadsheet or email me the correct VB code so I can put it in a 
spreatsheet and make it web accessible.

> Martial Tarizzo
> Physics Teacher - Metz - France
> 
>>The one problem I'm having is that I don't seem to be able to catch 
>>SchemeError events. Being able to would really help in debugging. I 
>>think this is the right way to do it but the code below is never
>>invoked.
>>
>>Private Sub MzCom_SchemeError(s As String)
>>     MsgBox ("Scheme Error: " + s)
>>End Sub
>>
> 
> 
> You have to modify/add the lines with ***********
> =========
> Dim initted As Boolean
> Dim WithEvents MzCom As MzObj *********************
> ' WithEvents -> you have now a new "object" in the left comboBox above the
> editor, *************
> ' with  MzCom_SchemeError as its event in the right one...
> ******************
> 
> Public Sub MzComREPL()
>     Dim sin, sout As String
>     initialize
>     On Error GoTo 20
>     sin = "'ready"
> 10  sout = MzCom.Eval(sin)
>     sin = InputBox(sout)
>     If Not sin = "" Then GoTo 10
>     Exit Sub
> 20  MsgBox ("repl: " & Err.Number & vbCrLf & Err.description)
>     initted = False
>  '   Err.Clear
>  End Sub
>   
> Private Sub initialize()
> Set MzCom = New MzObj  ****************** object initialization
>     On Error GoTo 10
>     If initted = False Then
>         MsgBox ("initting")
>         ' HAVE MzCom load some functions here
>         MzCom.Eval ("(current-directory " +
> Quote(slashify(ThisWorkbook.Path)) + ")")
>         initted = True
>     End If
>     Exit Sub
> 10  MsgBox ("init: " & Err.Number & vbCrLf & Err.description)
> End Sub
> 
> Private Function Quote(s As String) As String
>     Quote = Chr$(34) + s + Chr$(34)
> End Function
> 
> Private Function slashify(s As String) As String
>     Dim sl As Integer
>     sl = Len(s)
>     If sl = 0 Then
>         slashify = ""
>     Else
>         If "\" = Left$(s, 1) Then
>             slashify = "\\" + slashify(Right$(s, sl - 1))
>         Else
>             slashify = Left$(s, 1) + slashify(Right$(s, sl - 1))
>         End If
>     End If
> End Function
> 
> Private Sub MzCom_SchemeError(ByVal description As String)************** 
> ' ByVal mandatory, (ByRef is the default in VB) ******************
>  MsgBox ("Scheme Error: " + description)
> End Sub
> ========================