About Arbortext Styler > Extending Stylesheets > Editing FOSI Source that Contains a Reference to an Object
  
Editing FOSI Source that Contains a Reference to an Object
If you edit source that contains a reference to a property set, page set, header or footer object, TOC object or cross reference object for FOSI, and then subsequently delete or rename that referenced object in Arbortext Styler, you must return to the edited source and make the necessary changes to update the references. The rename and delete functions do not extend into edited source to search for references to the renamed/deleted object. The stylesheet will generate errors when the document is opened or previewed until the edited source has been fixed:
[A28138] Stylesheet has references to missing definitions.
These references will be ignored, use Styler's Validate
Stylesheet menu item to locate these errors.
However, the Tools > Validate Stylesheet option also does not extend into edited source and hence you will need to use a different method of error detection to find out the cause of the problem:
1. Export the stylesheet in FOSI format to an external file, via the File > Export > FOSI menu option.
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Your stylesheet must be set to use FOSI as the print/PDF engine to access this menu option.
2. In Arbortext Editor, select the exported FOSI as the stylesheet for the document.
3. View the completeness errors that are reported by Arbortext Editor/Arbortext Styler when the stylesheet change is made.
4. Locate and edit the erroneous references directly in the FOSI source: open the exported FOSI in Arbortext Editor, then use the Tools > IDs and ID References tool to locate the particular reference causing the error.
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The name of a charsubset in FOSI differs slightly from that of the corresponding property set in the Arbortext Styler stylesheet: spaces are replaced by underscores, and single underscores are replaced by double underscores. For example, the property set Title font in Arbortext Styler is listed as the charsubset Title_font in the FOSI source.
The same convention applies for page set names and the names of variables in TOCs and cross references.