# Error messages in UDO or Instr with nested if/then/else **URL:** \ **Category:** Newbies\ **Created:** [February 11, 2025, 11:10am UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023 "2025-02-11T11:10:10Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Lez](https://forum.csound.com/letter_avatar_proxy/v4/letter/l/c0e974/32.png) [@Lez](https://forum.csound.com/u/Lez)\ **Post date:** [February 11, 2025, 11:10am UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/1 "2025-02-11T11:10:11Z")
This keeps me annoyed for some time now, because I don’t seem to be able to work out the problem. It would really help if there was some kind of ‘switch’ control like in C, C++, Swift, etc in the CSound language. It would make code like this a lot more readable. I’ll add some sample code. Don’t bother about the contents, it’s about something I probably do wrong constructing this UDO. I also tried to use this construction inside an instrument, but I get the same error message for **endin** I checked this code a million times, but as far as I can detect there is nothing wrong with it. All if/then/else conditions are closed, no typing errors, but I get the error message: **error: syntax error, unexpected UDOEND\_TOKEN (token “endop”) from file** I work in CSoundQt, maybe it has something to do with that opcode SetNewKey, 0, 0 iKeyDecision random 0, 4.999 iKeyIntDec = int(iKeyDecision) iProgDecision random 0, 3.999 ;Randomly decide what ChordProgression to play iProgIntDec = int(iProgDecision) ;Decision structure to determine the giProgression chord order. Currently only 4 progressions are defined if iProgIntDec == 0 then giProgression = giMajMinMod1 elseif iProgIntDec == 1 then giProgression = giMajMinMod2 else if iProgIntDec == 2 then giProgression = giMajMinMod3 else giProgression = giMajMinMod4 endif if giCurrentKey[1] == 0 then ;Major key modulation if CurrentKey is major (currently 6 possibilities are defined) if iKeyIntDec == 0 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[2] giGoalKey[1] = 1 elseif iKeyIntDec == 1 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[4] giGoalKey[1] = 0 elseif iKeyIntDec == 2 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[4] giGoalKey[1] = 1 elseif iKeyIntDec == 3 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[6] giGoalKey[1] = 0 elseif iKeyIntDec == 4 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[4] giGoalKey[1] = 0 else ;if iKeyIntDec == 5 then giGoalKey[0] = giCurrentKey[0] + giMajorScale[7] giGoalKey[1] = 1 endif endif if giCurrentKey[1] == 1 then ; In second case the CurrentKey Scale is minor if iKeyIntDec == 0 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[1] giGoalKey[1] = 0 elseif iKeyIntDec == 1 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[2] giGoalKey[1] = 1 elseif iKeyIntDec == 2 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[3] giGoalKey[1] = 0 elseif iKeyIntDec == 3 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[4] giGoalKey[1] = 1 elseif iKeyIntDec == 4 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[6] giGoalKey[1] = 0 else ;if iKeyIntDec == 5 then giGoalKey[0] = giCurrentKey[0] + giMinorScale[7] giGoalKey[1] = 1 endif endif endop ---
**Author:** ![rory](https://forum.csound.com/user_avatar/forum.csound.com/rory/32/7_2.png) [@rory](https://forum.csound.com/u/rory)\ **Post date:** [February 11, 2025, 11:45am UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/2 "2025-02-11T11:45:11Z")
This doesn’t look right: > [@Lez](#): > > else if iProgIntDec == 2 then ---
**Author:** ![Lez](https://forum.csound.com/letter_avatar_proxy/v4/letter/l/c0e974/32.png) [@Lez](https://forum.csound.com/u/Lez)\ **Post date:** [February 11, 2025, 1:56pm UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/3 "2025-02-11T13:56:34Z")
Thanks Rory, I have been concentrating on the second block of nested if/then/else and had probably a blind eye for the first part. This solved it. But it still is a pity that there isn’t a control function like “switch” in the CSound language. I code in other languages as well, it is a tool that I use a lot and it results in very readable code. Thank you ---
**Author:** ![rory](https://forum.csound.com/user_avatar/forum.csound.com/rory/32/7_2.png) [@rory](https://forum.csound.com/u/rory)\ **Post date:** [February 11, 2025, 2:56pm UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/4 "2025-02-11T14:56:13Z")
I agree. `switch` would be nice. But in the meantime, you could probably benefit from formatting your code a little better 🙂 Those if/else blocks are hard enough to read with indentation, but are a complete nightmare without it. ---
**Author:** ![Lez](https://forum.csound.com/letter_avatar_proxy/v4/letter/l/c0e974/32.png) [@Lez](https://forum.csound.com/u/Lez)\ **Post date:** [February 11, 2025, 4:34pm UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/5 "2025-02-11T16:34:22Z")
I’m sorry, but the layout got lost when I copied the code into the textfield. In the actual code everything is indented and every “if” statement has its own layout. For my next question I’ll pay a bit more attention to what it actually looks here… ---
**Author:** ![rory](https://forum.csound.com/user_avatar/forum.csound.com/rory/32/7_2.png) [@rory](https://forum.csound.com/u/rory)\ **Post date:** [February 12, 2025, 8:59am UTC](https://forum.csound.com/t/error-messages-in-udo-or-instr-with-nested-if-then-else/2023/6 "2025-02-12T08:59:25Z")
That makes sense. I’ll put my formatting police hat away now 🤣