Commits changes to the current command to the command definition. Subsequent calls to the command need to match the new definition of the command. In other words, this allows you to change the behavior and signature of a command after it is added with XSIApplication.AddCommand.
Alternatively, you could remove the command completely (with XSIApplication.RemoveCommand) and redefine it from scratch.
Warning: Extra care must be taken when you update the definition of a command because it might break scripts that are relying on it.
Note: You cannot update the definition of built-in commands.
• See Command.Update.1.js
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