JavaScript and clean coding

25 Jun 2014

\[ \dfrac{TeamDiscipline}{LanguageExpressiveness * NumberOfCollaborators} = Productivity\]

tl;dr An expressive, loosely-typed language, like JavaScript, can only be used in a large scale project if standards, however arbitrary, are rigorously and ruthlessly enforced.

Lately, I've been reading Robert C. Martin's book Clean Code. I've also been engaged in a long-running discussion with a very knowledgeable friend about the merits of Node.js compared to Java for large scale applications.

He's not a fan of Node. My guess is that Martin wouldn't like it much either. But I am unsure.

The problem seems to be this: JavaScript is a very expressive language. A lot can be done with just a few lines of code. It is also a loosely-typed language. It is, overall, not a very rigid language. To be maximally precise, if there is a problem to be solved, there will be dozens of ways to solve it in JavaScript, with some being very clearly worse than others but not one being unequivocally the best. The choice of using a functional style, a protypal object-oriented style, or aping a classical object-oriented style (using constructor functions to simulate classes, etc.) is left up to the developer.

Which means, in a collaborative environment, that it is left up to each and every developer.

Not only that, but even if a choice is made, nothing stops a developer from being inconsistent, from being functional in this part of the code, more classical over here, or even avoiding the OO features of JavaScript entirely to be boring and procedural. JavaScript allows you to do it.

This is a problem. Obviously, you'd have to be a really bad developer, or maybe just a wickedly devious one, to flip flop from style to style like this. No one would do that, right?

Sure. But a single devious or supremely incompetent developer is not the problem. The problem is a team of developers, none of whom is totally incompetent or devious, but each of which is sometimes less competent -- or, more precisely, less disciplined -- than he or she could be.

Spontaneous Order & A Million Acts of Care

Bringing me to Martin's book. I haven't finished it yet. I loved the forward; especially this quotation:

Quality is the result of a million selfless acts of care -- not just any great method that descends from the heavens.

The reference need not to a million acts of a single individual, but to many different acts by many different people. If care is lacking from one or two of those acts, the difference in quality may be negligible. If there is a pervasive lack of care, disaster will result.

How to explain this? F.A. Hayek described spontaneous order, the idea of an overall order emerging from the acts of individuals, most or all of whom did not seek to create that order. A million selfless acts of care add up to something that is more than the sum of all those choices.

Conversely, too many "isolated" uncaring acts can corrupt a process and undermine the final product, without any individual actor being grossly incompetent or malicious. All that is required is a sufficient number of uncaring acts, each isolated from all the others. The more collaborators there are, the more this can occur -- that is, unless team discipline prevents uncaring acts, or provides a fix for them before their effects multiply.

Let's just call this effect -- lots of individual acts making a product worse than any individual actor intended, and even making the product worse than the competence or incompetence of any individual actor can explain -- spontaneous disorder. For proof that spontaneous disorder exists, I invite the reader to witness a meeting of any academic committee.

Collaborators vs. team (or average) discipline -- that explains part of my equation. There comes a point where average discipline is insufficient to overcome the sheer entropic impact of the combined interactions of the actors. Nothing can be done about that except to maintain discipline, and for that, Martin's book is an excellent place to start.

Spontaneous Disorder In Spite of Discipline

But what about the other variable, language expressiveness?

It seems to me that language expressiveness, in the sense I earlier described it, can cause spontaneous disorder despite discipline. If there is a single way to solve a problem, then by definition that is the most efficient way to solve it. If there are multiple ways to solve a problem, but one is theoretically more efficient, then a sufficiently competent team will eventually arrive at that solution.

But if there are multiple ways to solve a problem, and none is clearly more efficient than the other, then the choice between the solutions will be somewhat arbitrary. The arbitrariness will lead to inconsistency. Why solve all problems of type X in the same way? Why not solve some problems of type X in one way, some in another? Will this inconsistently inevitably emerge, given a sufficiently expressive language? I am not sure. If so, that is a problem for JavaScript, because JavaScript is very expressive.

If I am right, large JavaScript projects will have a tendency toward spontaneous disorder, even with a disciplined team. This is because discipline is itself insufficient to provide answers to the questions an expressive, loosely-typed language raises. No amount of discipline -- none of the principles Martin articulates -- can provide a definitive answer to how a complex problem should be solved in JavaScript.

It is also clear that the severity of this problem scales up with the number of developers. More developers equals more arbitrariness, more decisions made with insufficient reason. One developer can be satisfied doing things one way, just because he has decided that is how things shall be done. Two developers may come to an agreement between them. Three or more? Must management ultimately decide?

That may, in fact, be the answer. When market forces are insufficient to provide an important good, there are those who believe the government ought to provide it. Similarly, when a million selfless acts of care cannot yield quality, then maybe it is time for a higher authority to set standards, no matter how arbitrary those standards are.