on-save-file (augmentable only) in editor<%>

Called just before the editor is saved to a file, after calling can-save-file? to verify that the save is allowed. See also after-save-file.

• (send an-editor on-save-file filename format) -> void
     filename : path
     format : symbol in '(guess standard text text-force-cr same copy)

  The filename argument is the name the file will be saved to. See load-file for information about format.

  The filename argument cannot be a string; it must be a path value, section 11.3.1 in PLT MzScheme: Language Manual.