Question on ln in a for/next loop

Question on ln in a for/next loop - Printable Version

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RE: Question on ln in a for/next loop - Pete - 09-13-2024

Quote:name that tune: Tie A Yellow Ribbon Around The Old Oak Tree

Can you name the singer who made it famous?

Tony Orlando and Dawn. I knew them personally. They used to frequent my father's store.

Now a math question:

Q: What does Fake News + Phony Politicians =

A: Real Problems

Pete

RE: Question on ln in a for/next loop - Kernelpanic - 09-13-2024

The global "ln" was probably passed to a Procedure(Sub). - A local "ln" is only known in this subprogram and has no effect on the program outside.

Why it is -2?

Does the local variable also come before a "shared variable" in the main program? Test it! Tongue

Code: (Select All)



'Beispiel lokale Variablen - 13. Sept. 2024



$Console:Only

Option _Explicit



Declare Sub Beispiel()

Declare Sub Beispiel2(ln As Integer)



Dim As Integer ln, speed(10)



For ln = 1 To 10

  speed(ln) = ln

  Print speed(ln)



  'Sonst ist ln = 11

  If ln = 10 Then

    Exit For

  End If

Next

Print: Print ln



Locate CsrLin + 1, 2

Call Beispiel



Locate CsrLin + 1, 2

Call Beispiel2(ln)

End



Sub Beispiel

  Dim As Integer i

  Dim As Single ln



  For i = 1 To 10

    ln = i * 1.36

    Print Using "##.##"; ln

    Locate CsrLin, 2

  Next

End Sub



Sub Beispiel2 (ln)



  Dim As Integer ln



  'Das lokale "ln" geht vor dem globalen

  ln = ln - 2

  Print ln

End Sub

RE: Question on ln in a for/next loop - bplus - 09-13-2024

Why -2? because when you Dim ln as Integer inside the subroutine you set it to zero.

Comment that line out and all is as expected.

RE: Question on ln in a for/next loop - Kernelpanic - 09-13-2024

@bplus - correct in principle. It is -2 because every new uninitialized variable in Basic is automatically initialized with zero. Zero minus 2 is . . . -2.