Specifying Direct anipulation within

Language spectfic editors, since they are cognisant of the syntax and semantics of the programming language they manipulate, -should provide a number of advantages for software developers. Howevel; they have not been widely accepted by software developers for serious soflware development. In other domains, such as drawing and VLSI design, direct manipulation editors (which are also cognisant of the entities they manipulate) have proven to be successful. Consequently, the incorporation of direct ma-’ nipulation into program editors is worthy of investigation. Furthermore, the generation of editors from descriptions of the language to be handled and the editing mechanisms to be used has a number of advantages. Thus, this paper outlines a technique for specifying direct manipulation editing of programs which is amenable to the generation of language speciJc editors from a spectfkation of the desired editing mechanisms. l