Help on Goto

Comments

• Sawmiller Posts: 276

  2006-08-20 15:11 edited 2006-08-20 15:11

  watch your indenting
  
  case k
  
  ·· $40 : case Btn
  
  ··············· Btn1 : K == $40 and Btn == Btn
  
  ················Btn2 :
  
  ··············· Btn3 :
  
  ·· other :· do other stuff if K <> $40
  
  
  somthing·like this nested case if your looking for 2 things ,irst k = $40 and then which button ?
  of course you could use a if statment for the outside case if your only looking for $40 before checking for btn states
  
  dan
• Mike Green Posts: 23,101

  2006-08-20 15:17 edited 2006-08-20 15:17

  You can't do this directly in SPIN ... There are no GOTOs. This does look like a great table driven problem (although you didn't say much about the "K"s). You don't give any information about the range of K values or the total number of "BtnN" choices. One thought would be a table with an entry for each K value that contains the K value, the value of N for each K, and a list of N values representing the BtnN choices. One entry for the example you gave, but with a N of 5 and BtnN values from say 5 to 9 (they don't have to be in order).
  

  Table byte     1                               ' number of entries
           byte     $40, 5, 5, 6, 7, 8, 9
  
  

  
  
  You'd have a whole bunch of such entries, search them with a little routine:
  

  PRI search(K,Btn) | i, p
    p := 1
    repeat i from 1 to Table[noparse][[/noparse]0]
      if K == Table[noparse][[/noparse]p]
        return Table[noparse][[/noparse]p+1+Btn]
      else
        p += Table[noparse][[/noparse]p+1] + 2
    return 0
  
  

  
  
  You could add range checking on the value of Btn in the line after the "if". You could substitute some other default action if K isn't in the table. You'd follow a call to this with a CASE statement for the actions
  

    CASE search(Kvalue,BtnValue)
      0: ' default
      5: ' K of $40, Btn1
      6: ' K of $40, Btn2
      ....
      9: ' K of $40, Btn5