Monday, October 27, 2014

Some Thoughts about Source Code, Design Decisions, and Documentation - Markdown, DocBook, and the Igneous-Math Source Tree

Having completed a finals exam for an electronics course I'm enrolled in, I've published the Igneous-Math source code to GitHub, tonight [igneous-math]. The Igenous-Math source tree is currently in the beginnings of its 1.3 edition, focusing on definition of unit conversion formulas. Though, simply, I do look forward to the beginning of the prototyping for the 1.3 edition -- have been bouncing around a few ideas, namely to make reference to the Garnet KR system [garnet] for its formula modeling as applied in KR schema objects and as may be applied in arbitrary Lisp code -- however, I would like to make some more refined documentation for the source tree, also -- now at the end of the end-of-week sprint, in developing that source tree.

In developing the Igenous-Math system, presently, I'm using GNU Emacs as an IDE, together with a system named SLIME, in its Emacs Lisp components -- and in its corresponding Common Lisp components, named SWANK -- focusing mostly on SBCL as the Common Lisp implementation, but  I've made some testing of the source tree using CCL, also. In applying those software components, together with the Git changeset management system, in an installation of KUbuntu within Virtualbox, I think it makes for a fairly comfortable development environment -- it's certainly easy to test the Common Lisp source code, using SLIME+SWANK, and simultaenously so, when running the Linux platform and the Microsoft Windows platform, using Virtualbox. Of course, I would like to make a modicum of effort to ensure that the Igneous-Math system could be a system that other software developers might feel comfortable to use, too, at least once it would be at its first branch-level revision.

Throughout this week's short sprint in the development of the Igenous-Math source tree, I've been making some copious notes in the source-tree -- something to remind oneself of a bit of a sense of context, in relation to any source code approximate to the comments, in the source tree. Of course, that can seem convenient enough, from one's own perspective in developing the source tree. As far as the availability of the source tree, I understand that it might seem to leave something lacking, though, under the heading, "Documentation."

So far as what may be accomplished in developing the documentation of a source tree, I think:

  1. An item of documentation may serve as to explain one's design decisions, to oneself, as well as towards the respective audience or user base
    • That rather than developing an axiomatic mode, with regards to documentation, alternately one may seek to explain one's rationale, to the reader, as with regards to any specific design decisions made in the development of a software system -- that not only may the documentation serve to explain so many design decisions, but it might alsoserve to place those design decisions within a discrete sense of context, conceptually.
    • Inasmuch, candidly, an item of documentation may serve as to explain one's rationale to oneself , at a later time -- thus, perhaps serving to ensure something of a degree of design consistency, with regards to one's rationale, in the design of a software system.
  2. An item of documentation may serve as to describe any set of things presently developed within a source tree -- thus, making a sort of simple inventory of results.
  3. Furthermore, an item of documentation may serve as to describe any number of things planned for further development, within a source tree and within any related software components
  4. That an item of documentation may serve a necessary role in ensuring that the software code one has developed can be reused, as by others and by oneself, extensionally.
Although the Igenous-Math system is published under a license as free/open source software, but candidly, I would not wish to have to ask the reader to peruse the source tree, immediately, if the reader may simply wish to understand the natures of any set of software components published of the source tree. 

So, perhaps that's towards a philosophical regard about documentation. Corresponding to a philosophy about documentation, there would also be a set of tools  one would apply, as in developing a  set of documentation items as -- altogether -- the documentation of a project serving as a sort of content resource, within a project.

Though I have given some consideration towards applying a set of complex editing tools and structured formats for documentation -- had made a note, towards such an affect, in the Work Journal, at a time when I was considering whether I'd wish to use the DocBook format and the DocBook toolchain for documenting another software system I've developed, namely AFFTA -- however, tonight I'm more of a mind that it would be just as well to use the simple Markdown format, in canonical Markdown, or in the more structured MultiMarkdown format. Markdown may serve as a relatively accessible document format, for simple notes and documentation within a software source tree.

DocBook, in its own regards, would be a more syntactically heterogenous format to integrate within a software source tree. In a sense, DocBook doesn't look a whole lot like text/plain, though XML is a plain text format.

A DocBook XML document, in particular, can be written with any existing text editor, such as Emacs, or with a specialized XML editor, such as XXE, the XMLmind XML Editor. In Emacs, specifically, the nXML Emacs Lisp extensions can be of particular utility, when writing XML documents [JClark][NMT].  Together with a complete DocBook toolchain [Sagehill], the DocBook schema [TDG5], and DocBook editing platform, the documentation author would be able to create a well structured and comprehensively descriptive reference document for a project.

As something of a rosetta stone for document formats, there's also Pandoc

Presently, MultiMarkdown is the format that I prefer for developing so much as the README file for the Igenous-Math codebase.  There's even a nice, succinct guide page available about MultiMarkdown [ByWord] explaining the additional features provided with MultiMarkdown, as it extending on the original Markdown format.  For a purpose of delineating the simple "To Do" items of the Igneous-Math codebase, and for providing anything of an external, "High level" overview of the codebase -- such as one would encounter of the README file for the source tree, as when viewing the source tree, in its web-based GitHub presentation --  MultiMarkdown may be sufficient, in such application. Candidly, to make such a simple presentation about the source tree, using DocBook -- for one thing, the DocBook format does not so readily allow for the author to control the formatting of the documentation. With DocBook, perhaps there's something of a tradeoff for semantic expressiveness, in lieu of any easy visual design for documentation. By contrast, Markdown allows for an easy control of the visual layout of the documentation, though the Markdown syntax offers only a relatively small set of markup features.

Secondly, the toolchain automation that would be required to simply publish a README file, in Markown format, if from a source document in DocBook format -- such a tranformation model would certainly be less than ideal. It would allow for a transformation of only a limited set of elements from the DocBook schema, and though it may serve to produce some relatively accessible documentation -- accessible to the sighted web visitor, at least -- but one may find it difficult to explain to oneself: Why one would transform a source document from DocBook format, into a source document in Markdown format. Candidly, the GitHub presentation for Markdown is a feature extending of Github's own support for the Markdown format. One might think it's unsurprising, if there's no such specific support for all of XML. in the GitHub web interface -- XML is a very broad markup format, in all of its structural extensibility and its text/plain format

So, if it's possible to effectively produce a snapshot of one's point of view, at a point in time, then here's my view about the Markdown and DocBook formats, considered in relation to development of the Igneous-Math source tree.

It might bear a footnote, also, that the MultiMarkdown format is supported on Ubuntu platforms, in the libtext-multimarkdown-perl package. For integrating MultiMarkdown with Emacs MarkdownMode, there's some advice by David from Austin, TX [ddloeffler]