When a Dictionary Is Not Available

AppleScript uses double angle brackets in a Script Editor script window when it can't identify a term or can't display a value directly. The first word within the double angle brackets can be any of the following: event , property , class , data , preposition , keyform , constant , or script . The second word varies depending on the context.

AppleScript can not display a term in English if isn't a part of the AppleScript language and it isn't defined in an application or scripting addition dictionary that is available when the script is opened or compiled. That usually happens for one of two reasons:

A required application or scripting addition dictionary isn't physically present when the script is opened or compiled (possibly because the script was compiled on one machine and opened on another).
A required application or scripting addition dictionary is available but doesn't support a term used in the script (most likely because the dictionary is from an older version of the application or scripting addition).

As an example of a missing dictionary, suppose you create a script that uses the Display Dialog scripting addition command, then open the script when the Standard Additions scripting addition (which includes the Display Dialog command) is not present. AppleScript replaces the words display dialog in the script with «event sysodlog» . In this case, you should make sure the Standard Additions scripting addition is present in the Scripting Additions folder (which is located in the System folder) before attempting to compile or run the script.

As an example of a missing term, suppose you create the following script, which uses the delay scripting addition command, available starting with Mac OS 8.5:



 
display dialog "Ready to test your patience?"

set myDate to current date

delay 4

display dialog "4 second delay on " & (date string of myDate) & "."

This script displays a dialog, waits for the user to dismiss it, then delays for four seconds before displaying a second dialog that includes the current date. If you save this script as text and compile it on a machine running Mac OS 8.1, the Script Editor will display the following:



 
display dialog "Ready to test your patience?"

set myDate to current date

«event sysodela» 4

display dialog "4 second delay on " & (date string of myDate) & "."

AppleScript converts the term delay 4 to «event sysodela» 4 because the Delay scripting addition command is not available with Mac OS 8.1. Without the Delay term in an available dictionary, AppleScript doesn't have an English language term to display. The script compiles, but won't run correctly on the machine with Mac OS 8.1 because the Delay command isn't available. If you save the compiled script, then move it to the original machine with Mac OS 8.5, it will run correctly. If you recompile the script on the original machine, AppleScript converts «event sysodela» back to delay 4 .

For related information, see Entering Script Information in Raw Format.