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by edejong 2040 days ago
I tend to think people underestimate the hidden complexity of sequential programming. Each statement has a potential, opaque effect on the complete state.

To prove anything in the OP solution would be extremely complex. To extract new knowledge and abstract the solution in the future would be nearly impossible without a complete rewrite.

For example: what if we need logging? Timing of the steps taken? A list of dish washing tasks generated? Parallelism in the tasks, given an extra cook? Exception control? Unit testing of the dough?

Adding an extra recipe is not the only possible new requirement you can have. Anticipating and preparing the right abstractions, that’s what good software engineering is about.

2 comments

"Anticipating and preparing the right abstractions, that’s what good software engineering is about."

I find this a rather surprising statement. It sounds almost like something from some weird parallel universe. In my universe I generally take for granted that anticipating abstractions is not something that actually works.

Let me give an example. Some years ago I was working on some code that was writing and reading data from a database. A colleague said that we need validation so every field that can be written to the database needs to have the ability to have a validation. So, optionally a validate function can be attached to each and every database field. I was against it at the time because as I stated I do not believe in anticipated abstractions. But the colleague was convinced that it was necessary and wrote this. A few years later indeed validations had been added but literally all validations where about properties that a set of fields together should have and literally none of them were about single fields. At some point I just deleted the single field validator. It had been there for years but it never was anything besides completely useless.

To me anticipating abstractions is a recipe for all kinds of over-engineering. The need for abstractions arises as more requirements need to be fulfilled and when writing those one should probably think about what is likely going to be desired in the future but anticipating them before it is needed is something I have given up a long time ago.

I absolutely agree with this. I always like to say, the best way to make code extensible in future is to make it do its current job as simply and clearly as possible.

If you leave a hook in for some feature you "know" is coming you'll only screw it up - either that feature won't be needed or it'll look different than you expect. Your field validator is a great specific example, I think I'll use that one in future.

(A corollary of this though is that you have to be happy to ruthlessly refactor existing code when a new requirement actually does enter the scene, because of course that requirement was deliberately not prepared for in the existing code.)

A hook is not an abstraction. A validation function is not an abstraction.

An abstraction would be to say: "These programming statements are actually objects." Or, the time and ordering constraints implied in this program should be explicit.

In addition, I was talking about anticipation and preparation of abstraction. Not the actual abstraction.

> A hook is not an abstraction.

By "hook" I didn't mean anything specific, like a React Hook. What I meant was adding some extra abstraction that has no purpose except for some future feature. For example, taking a class that works perfectly well on its own (let's say Rectangle in a drawing program) and separating it into a base and derived class (let's say Shape and Rectangle) in anticipation of a feature in a future release (next time we're going to add a Pentagon class too and that'll need to derive from Shape). If you don't consider that change to be adding an abstraction, then I suppose we just have different ideas of what an abstraction is.

> In addition, I was talking about anticipation and preparation of abstraction.

I wonder if you've just used a word that doesn't reflect what you really mean. Maybe you just meant designing and creating an appropriate abstraction for the current requirements? "Anticipate" would be the wrong word for that.

"Anticipate" literally means making an educated guess about some future event before information about it becomes available. Most of us have experienced other devs aniticipating future requirements, and creating abstractions in response to that anticipation, and the inevitable negative fallout of that. So seeing "anticipation ... of abstraction" is bound to generate a negative emotional response.

Programming in my world is about anticipating abstractions, without actually abstracting. We write code for it to be changed. We know to a certain extend how the specifications, design and code are likely to change over time. We anticipate the kind of abstractions needed to accommodate that change.

This in turn influences the choice of programming language, unit testing, naming, modularization, infrastructure...

Just as a simple counter example: I write my code so I minimize the amount of state and provide good type information. The advantage is that future (re-)composition in other abstractions of the code will continue to work.

If your familiar enough with the problem, you can usually predict fundamental requirements and design in anticipation of them.
Boy, who has time to be familiar with a problem anymore? I used to be familiar with problems, now I just slug through problems created by other people.
How do you have their problems become your own?
I think there is an important difference between anticipating abstractions and actually abstracting.

In your example, you were actually implementing an abstraction and anticipating a future use. That is something completely different.

What I am trying to bring across is: there are multiple 'simplest' solutions. It helps to know how, in the future, you are expecting to abstract away from that solution to newer 'simplest' solutions.

For example, one might want to use a FP-ish approach, because simplest solutions within that space tend to abstract better than an OOP approach. Or in the recipe example, we could have modeled the steps as objects with dependencies. Given the right programming language, that solution might be as simple as the OP, but provide many more extension points.

This is the essence behind YAGNI. I think it's something everybody disbelieves to begin with and only learns through suffering the pain of their own mistakes.

At least, I've really struggled to convince people that it's true until reality hits them in the face.

I completely agree. One thing I would add that you shouldn't anticipate abstractions, but find them through business domain analysis. Exactly like OP missed that there's ingredients, recipe and equipment.
Thanks. I intentionally stayed outside of the business domain, since I believe it is a subset of the problem domain. But, then again, I agree the orientation should be around the added value and as such, most likely, the business domain.