This paper considers aspects of man-machine interaction to enhance the use of a text editing system. Two features were seen to be of major significance: random access to pages of text by names; and the ability of the user to dynamically control the performance of editor commands, called in the text “continuous control.”

Random access to text is not new; however, the use of names as opposed to numbers is uncommon and was found to improve the utility of the editor. Continuous control offers the advantage of feedback to the user--he is always aware of what the editor is doing on his behalf, and he may exercise control at any time, even when a command is in progress. The authors found that additional values of the continuous control design were the simplification of the editor’s code design and the reduced severity of actions caused by human error in issuing commands.

I found the paper interesting since one seldom encounters investigations into editing. Although editing is one of the most common activities in interactive computing, editors are usually taken for granted. I do have two criticisms of this work:

• (1) I would have preferred a discussion of the intended use of the editor. The design of a word processing editor is radically different from that of a programming language editor. Do the concepts presented here (e.g., continuous control) have relevance in both environments? This sort of question should be addressed.

• (2) The computing environment was minicomputer based. Since microcomputers offer the superior terminal interface to the user, more mention of work done on microcomputers is in order. For example, some of the design ideas mentioned in the paper have been implemented in current products commercially available on microcomputing equipment.