Tag Archives: TPL

Keep API Usage Simple

One lesson that I’m appreciating more every week is that old acronym, K.I.S.S. – Keep It Simple, Stupid. Simple code is best. The highest cost of most software is maintenance—and you don’t want maintenance to include a lot of “how the heck does this work?”

This simplicity does not apply to just your own code. Most API frameworks provide multiple ways of doing things, but if you don’t need it, don’t use it.

For example, I’ve been working a lot with the Task Parallel Library, and it’s great – it really is an awesome way of doing asynchronous programming. However, when you get to continuations, there are so many options, it can quickly make your code a bewildering mix of usage patterns, if you’re not careful.

You can have continuations called only when the task fails, or is canceled, or only when it succeeds, or only when it does not succeed. You can chain continuations, cancel them, and there are all sorts of scheduling options, and much more.

This API is powerful, and I’m grateful it’s all there, but when you need to have a large team work on a single code base, it’s helpful necessary to enforce some simplifying constraints. One thing we’ve done, specifically with the Task Parallel Library, is to require everyone to use just one of the many possible patterns. This way, no matter what part of the code we’re looking at, we can understand exactly how Tasks work. It takes the guesswork out, and reduces maintenance costs. This kind of thing is especially critical for complex areas of the code – i.e., asynchronous programming.

Takeaway: you don’t have to use every possible API feature or pattern—just pick one and enforce consistency and simplicity.