Date: Thu, 5 Nov 92 09:55:34 +0100 From: Tim Berners-Lee <firstname.lastname@example.org> Message-Id: <9211050855.AA02508@www3.cern.ch> To: email@example.com Subject: Format conversion with NeXTStep 3.0 Here's an excerpt from the NeXT Nugget news digest, talking about aspects of NeXTStep 3.0 which developers ought to take into account. (I don't think WonderFormat is a MIME type ;-) - Filter services A Filter service is a new 3.0 type of Service which has no menu item but supports the ability to convert a piece of data from one type to another. Every application can take advantage of filter services when opening files (via +typesFilterableTo: if it can open a standard type, like RTF) and when importing data via copy/paste or dragging (via +imagePasteboardTypes). Other applications can provide filter services: for example, if you have some code which converts your document format [the WonderFormat] to RTFD, then you should provide this functionality as a filter service. Another application which understands RTFD but not WonderFormat can still import WonderFormat documents and the filter service will do the work of the conversion. The other advantage of providing a filter to ascii is that your documents then become indexable by Digital Librarian. See the 3.0 Appkit Release Notes and the Pasteboard spec sheet for more information on: +typesFilterableTo:, +newByFilteringFile:, +newByFilteringData:, +newByFilteringTypesInPasteboard:.