An SGML-based programming environment for literate programming

8 it to compile it afterwards. However, programs are text, so they can beneet from recent results in document research. We propose a new underlying structure for literate programs, based on SGML. As a result , we will use SGML tools to view and modify literate programs. These tools will isolate programmers from the low level structure of literate programs. Moreover, literate programming can be easily extended to use other types of information such as Z formal speciications, and in fact, literate programs could include any type of digital information.terloo. His current interests are in the area of software engineering, in particular software development environments and the application of text databases research to software repositories. 7 Z fragments do not include other fragments. Therefore, it is only necessary to extract all Z fragments and reorder them according to their numeric tag. During both \tangling" processes all macro usages are expanded and all SGML tags are removed. The nal result is a text le that can be processed by a compiler or checker. 3.4 Editing SGML literate programs ASCII text with embedded SGML is hard to read, and thus editing will be a cumbersome and unpleasant task. Remembering the speciic tag set for segments of text or code, and placing the tags to ensure a syntactically correct document will also create problems. In addition , if the tagged document is edited with a text editor, then all the visualization information that can be generated from the tags will not be present. Syntax-directed editors such as Rita 2], the SoftQuad Author/Editor 12] and editors produced by the Cornell Synthesizer 9] could be used to address some of these issues. For example, Rita uses a form of DTD and style sheets to support editing of SGML tagged text. At any point in the document this editor will prompt the user with a list of syntactically acceptable tags. The tags are also separated from the text so the program looks quite \natu-ral". In addition, the style-sheet can be used to maintain much of the visualization information which is critical to the understanding of the literate program. Another approach to editing is used by the Waterloo Database Browser 16]. It exports a section of an SGML document to a WordPerfect 2 le, and then formats the output text according to a WordPerfect style-sheet for the document. Then, the user uses the word processor as an …