Computers, Open-source, Personal, Ruby, Software, Thoughts, Web

Another Helping of Abstraction, Please

Rails 3.1 is soon to be released, and with it comes two new abstraction libraries – CoffeeScript, and S(ass)CSS. These libraries are used to generate Javascript code, and CSS definitions respectively. While abstraction libraries are nothing new to Rails, the inclusion of two more got me thinking about the direction that Rails stack is heading.

CoffeeScript’s syntax seems to be to make Javascript as Ruby-ish as possible. It describes Javascript’s curly braces and semicolons asĀ embarrassing.

SCSS aims to address some of the repetitive elements of CSS through the use of variables, nesting, and mixins. This feels more acceptable to me than CoffeeScript, but my first encounter left me burned.

A few other abstraction libraries of relevance: Haml aims to generate HTML without the use of HTML tags. Additionally, Squeel‘s (MetaWhere 2.0) aim is to remove all SQL from your projects.

So what am I bitching about? Abstraction is a good thing right? I see two categories of abstraction. The first being the “good” kind, that allow you to be completely ignorant of the underpinnings. For example, Ruby converting down into machine code.

The “bad” kind of abstraction are the substitution of a language with a DSL. This creates a lot of issues starting with development and debugging. In the case of CoffeeScript and SASS, you have to compile the DSL files into Javascript, and CSS files. I feel like this compile step is a step back from what we gain working with dynamic languages like Ruby, and Javascript to begin with.

Development in these libraries also requires that you understand both the DSL of the library, as well as being familiar with the language of the generated code. This additional skill requirement adds time to a project, and raises the entry bar for new developers. Its difficult to be proficient at a language, and a DSL that generates that language at the same time. A Ruby developer told me yesterday that he was surprised at how rusty his knowledge of SQL had gotten. Its shocking to me that a web developer would struggle with SQL, but I think its an accurate sentiment on which many Rails developers would agree.

Another casualty of abstraction is performance. Not only is the generated code sub-optimized relative to coding it by hand, it is also being run through through more system calls to get there. You can either compile up front (CoffeeScript, SASS), or you can incur this penalty on-the-fly (Haml, Squeel).

While none of the libraries are a requirement of web development, when working on a team that uses these technologies you are expected to produce consistent code. Even though these libraries let you execute “native” code, doing so is discouraged because of the availability of the DSL. The syntax for embedding native code (if its even allowed) is often cumbersome, and loses editor functionality such as syntax highlighting and parsing.

Since when did Ruby on Rails web developers stop working with SQL, CSS, HTML, and Javascript? I am beginning to feel like the Ruby camp is becoming the far left extremists of the web development world. The web is built on these core technologies, and the benefits of abstracting them doesn’t seem to outweigh the costs.