Opening a File and Selecting a Format Handler

The function handler:edit-file takes a filename and dispatches it to an appropriate format handler. A format handler takes a filename and opens a frame for the user to view or edit the file. If no handler is found for a particular format, then the file is opened as a raw text file, in a frame:text-info-file% object.

The function handler:open-file lets the user select a filename using finder:get-file, and then passes the name to handler:edit-file.