Zeus Tech Note
Lingo Error Messages

(This document last revised August 10, 1997)

Copyright © 1996-1999. Zeus Productions. All Rights Reserved.
Written by Bruce A. Epstein

Here are some of the most common Lingo Error messages, and possible solutions.

See also: Lingo in a Nutshell - Addenda to Appendix E

Syntax Error

This error indicates that Director expected a different form of your Lingo command, or different punctuation or that your grammar somehow confused Director.

• Check the spelling of all commands, variables and handlers
• Confirm the syntax for the command you are attempting to use, such as the number and order of expected parameters.
• Check for missing or mismatched parentheses or quotes
• Be sure you understand the use of quotes and the concatentation symbols.

Frame Not Defined

This error indicates that you have specified a frame that does not exist. For example, a label that is not present.

• Confirm that the label exists.
• Make sure you have spelled the label name correctly.
• Check for leading and trailing spaces in the label name, or spaces within the name itself.
• If specifying a frame number, confirm that the frame exists.
• If specifying the frame number with a variable, examine that variable in the debugger. Common errors include failing to initialize a local variable, or failing to declare a global variable as global, thus confusing it with a local variable.

---

Handler not defined

This error indicates that you have attempted to call a Lingo handler which does not exist, or you are performing a list operation on a variable that is not a list!

The error dialog shoud indicate which handler name it could not find. Once you have determined which handler it could not find, determine why.


If you are calling a built-in Lingo function:

• Verify the spelling of the command or function name. The documentation or Lingo menus within Director are sometimes mistaken, so don't trust them religiously.
  
  
• Verify that the function is indeed built into Lingo and does not require and Xtra. For example getOSdirectory() and other file operations require that the FileIO Xtra be installed.
  
  
  
• Verify that the function is indeed built into Lingo, and not a user-defined function. If it is user-defined, see below.
  
  
• Test the function from the Message window
  
  
• If using a Lingo List function, such as getAt() or setAt(), be sure that the first parameter passed to the function is a valid Lingo list. If using a list variable, verify its value in the debugger, or use the listP() function.

If you are calling a user-defined Lingo handler:

• Test the function from the Message window
  
  
• Check that your syntax is correct if calling a Lingo handler. The error may be caused by having, say, an extra space in the word "puppetSound". "PuppetSound" is one word, but if you typed it as "puppet sound", Lingo would look for a handler called "puppet" which doesn't exist.
  
  
  
• Try recompiling scripts to make sure the script you are reading corresponds to what Director is actually running.
  
  
• Check for misspellings off the handler name in your call, or in the handler definition itself. (i.e. make sure you spelled it the same in both places).
  
  
• Make sure that the handler is located in a script where it can be found. For example, it may need to be placed in a Movie Script so that Lingo can find it. If the handler resides in another movie, place it in an external cast that can be used by multiple movies in the project.
  
  
• If the handler is contained within an Xtra, verify that the Xtra is installed properly. For example getOSdirectory() and other file operations require that the FileIO Xtra be installed.
  
  
• If the handler requires an Xtra or XObject instance, be sure to instantiate the Xtra or XObject before calling the handler.

Wrong:

	puppet sound "mySound"

Right:

	puppetSound "mySound"

One parameter expected

This error indicates that you are specifying the wrong number of parameters for a Lingo command or function. Verify the syntax in the Lingo Dictionary. You may have supplied too many or too few parameters. In some cases you can use a dummy parameter, such as EMPTY or 0, as a place holder for a parameter

Wrong:

	alert

Right:

	alert "Hello"

	alert EMPTY

String expected

This error indicates that the Lingo command or function expects you to specify a string parameter and you are specifying something else, such as an integer. The error message should include additional information such as a number (in which case you specified an integer instead of a string), a "<void>" in which case the variable you used has not been assigned any value and is therefor "void".

You can force a type conversion by using the string() function.

If you are specifying a variable as the parameter, check the variable's value in the debugger, or by including a "put" statement in your script prior to where the error occurs.

If the variable you are using is a parameter that is being passed in , verify the function call arguments in the calling routine.

Verify the order and nature of the parameters in the Lingo Dictionary. You may have supplied too many or too few parameters.

Wrong:

	alert 7

Right:

  alert string(7)

Expected THEN

This error indicates that Lingo is confused by your syntax. Most likely, you have used an "IF" statement but forgot to include the corresponding "THEN" keyword, such as:

Wrong:

	if x = 5 

  		alert "Hooray"

	end if

Right:

	if x = 5 THEN

  		alert "Hooray"

	end if

...more to come...

Home (Spotlight) | Table of Contents | Links | Contact Info

Place an Order | Products for Sale | Licensing | Downloads

TechNotes | FAQs | E-Mail Zeus | GuestBook | Glossary



Copyright © 1996-1997. Zeus Productions. All Rights Reserved.