Documentation As a Creative Force

:: journal

Docs for the template package are coming together nicely. Architectural details are starting to jump off the page and I’m slowing down to fold them into the code before the initial release announcement.

Documentation is an essential part of my creative process. It exposes low-frequency patternsthe high-level concepts and techniques that enable the collective expression of disparate elements of a code base. Dialing into “the right frequency” inexorably leads to profoundly simpler code with more features and fewer bugs.

For template macros, I’ve got four technical documents cooking:

  • An API reference

  • An overview of the API

  • A README.md file

  • A blog-style introduction

In writing each one, I take a distinct perspective that supports the others. The first two comprise the reference manual, to be served by Racket’s official documentation repository. Together, they give a comprehensive account of the concepts, forms, and functions provided by the template package. The README.md file summarizes the project and explains how to install, use, and contribute to it. The blog intro makes a case for using the template package in other projects.

The API reference was easiest to start with, which is typical, in my experience. Reference material is special in the sense that hard facts tend to speak for themselves, freeing attention for higher level concerns like naming consistency and algorithmic robustness, without having to contextualize anything for a skeptical reader. With very few exceptions, everything in the API reference is illustrated with live examples. Having examples early in the drafting process helps keep the prose honest.

The blog intro is the pragmatic inverse of the reference manual. Its job is to convert the skeptical reader into an active user, so contextualization is really all that matters. This is the hardest part for me. To pitch template macros confidently, I need to know that what I’m saying is interesting, relevant, refutable, and true. Gaining sufficient clarity on any one of these criteria can be a challenge, but it’s almost always worth the trouble.

Just yesterday, I resolved an awkward tension between template variables bound to identifiers versus ones that aren’t. While struggling with the blog intro, I realized that it would be easy to generalize variable resolution from identifiers to any literal forms, including strings, regular expressions, and even hash keys! Once I understood the low-frequency pattern here— that all non-trivial transformations occur inside literal data forms— most of the prototype’s flexibilty became irrelevant. Trimming the fat is revealing a more compact, elegant, and robust core.