APP in Arbortext Styler > Integration of Arbortext Advanced Print Publisher in Arbortext Styler > Debugging .style Stylesheets with Arbortext Advanced Print Publisher > Debugging Tools
  
Debugging Tools
Arbortext Styler provides access to some features which can help stylesheet developers understand the formatting process and make informed decisions about how to update their stylesheets. These tools can be used to debug source edit code:
formatting.write() and formatting.output()
These methods output content onto the page and can be used to display any information. For example, you can use them to display variable values or XPath expression results or to indicate that a certain point in the code has been reached.
application.alert()
This method displays information in a popup alert message rather than taking space up on the page or affecting the formatting process.
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Alert messages can be helpful when formatting in Arbortext Styler’s print preview but they should be removed from the stylesheet before publishing.
Logs
If errors encountered in a publishing process and a print preview action are different, using APP’s logs to write information out to an external location can provide insight into the issue causing the errors.
Refer to Logs Generated by Arbortext Advanced Print Publisher for information.
Print preview
The APP Preview Window provides a number of tools, including block and frame guides, a grid, rulers, and the options available on the right mouse shortcut menu.
Arbortext Advanced Print Publisher — Desktop
You can save a previewed document from the APP Preview Window as an APP file and open it in Arbortext Advanced Print Publisher — Desktop for further investigation.