reading scala (functional programming) code

Based on some recent scala work and coming from imperative programming background, reading functional programming code is hard for me.

Why?

First, the code is rather terse and dense. The terseness derives from the ability to use operator-like characters as  function names. Java does not allow this so its usually easier to read the methods. Java's method name conventions generally make the code easy to read. This comes at the expense of verbosity. Scala can use normal function names as well and most libraries provide both the function name as well as a terse equivalent.

Second, its not always clear what design pattern is being implemented. Java has a few generally accepted approaches to writing code. Iterating over a list can only take a few forms. Creating some IO classes generally takes on only a few forms as well. The singleton pattern is implemented only in a few ways. If you are unfamiliar with functional programming, it takes awhile to recognize these types of patterns. There is alot noise in the functional programming community around monads. Monads have some special properties that make them useful in functional languages. I won't cover them here but there is a benefit for using monads. If you know something is a monad, then you expect it to behave a certain way and have certain types of methods. Putting aside details around their usage, monads help you understand functional code more quickly.

Third, functional languages are geared towards taking very small slices of code and building on them, layer after layer (or should I say, function after function). This type of fine-grained layering is much harder to understand than the coarseness of the java world. There are benefits to fine layering of course. However, a side effect is that it takes longer to get used to reading more finely-layered code.

I'm not saying that functional programming is hard or that's its not worth the effort to convert. It's not hard if you grew up with it.  Converting is harder if you are coming from an imperative background (fortunately its more easy for me since I have a lisp background).

Comments

Post a Comment

Popular posts from this blog

quick note on scala.js, react hooks, monix, auth

quick note on scala.js, react hooks, monix, auth Reactjs hooks finally came out of preview in a recent version of React. scalajs-reaction has had support for hooks since they were in preview. React hooks seem like the hot new thing but for me the question is, do hooks help improve your code by improving maintainability, time to market, TCO, etc.? Let’s take a look using authentication as an example and employ monix , a reactive observable framework that also builds on cats . We will assume we are building a SPA. Does it improve your code and make your application & development experience better? Auth Auth processing can be complex. Many react auth examples you find in blogs like to show how to use “react-routing” and “auth” as a switch that determines which routes are protected or unprotected. Protected routes show application specific data. Unprotected routes show login content . Based on storing a “User” object in the browser session/local storage, th
Read more

zio environment and modules pattern: zio, scala.js, react, query management

zio environment and modules pattern: zio, scala.js, react, query management This blog covers a zio-based fetch design for scala.js, react web applications. It heavily uses the zio “environment” feature to help motivate a point of view on the modules pattern in effect systems. At the end, I summarize some thoughts on ergonomics and complexity. This blog assumes a basic knowledge of zio and react. scala.js is just like scala so you mostly already know scala.js. This blog is a follow-on to previous blogs: https://appddeevvmeanderings.blogspot.com/2019/10/scalajs-react-fetcher-hook_48.html and https://appddeevvmeanderings.blogspot.com/2019/11/scalajs-and-react-suspense.html . I have been keeping an eye on and culling ideas from typscript/javascript fetching libraries that address query management concerns. The formulation below incorporates some of those concerns but does not try to comprehensively duplicate well established javascript libraries. I only care about
Read more

user experience, scala.js, cats-effect, IO

user experience, scala.js, cats-effect, IO This is not a complicated snippet but I wanted to ensure I remembered it. When creating a UI, say react for browsers, you will run into the “fetch” data problem. When you fetch data, you typically have a component that performs the fetch and acts as a cache for the result. The fetch component renders a child and passes along the data that was fetched (or the fetch state, etc.). Even with the upcoming react suspense mechanism that will make this a smoother user experience, you may have a flash of a “loading” indicator that shows for a moment before the content is fetched from the server. If the flash is too fast, it is visually disruptive. A shimmer mechanism for the UI my also not be the answer. Similarly, if the fetch request takes too long, you will want it to time-out and show an error message that the data could not be fetched or whatever is appropriate for feedback in your application. Generally, I use cats-effect
Read more