Comment by lvturner
2 years ago
Do the business requirements (fundamental assumptions around design to be more generic) of a bridge, car or airliner change dramatically over time?
I'd argue not.
Software design, in my opinion, is both a science and an art so my stance is that we need both the formal theory and science as well as the philosophy and that they shouldn't be viewed as mutually exclusive.
>Software design, in my opinion, is both a science and an art so my stance is that we need both the formal theory and science as well as the philosophy and that they shouldn't be viewed as mutually exclusive.
What formal theory have you ever used for designing your software? I would argue you've never used anything. Every abstraction you've ever made was likely a gut feeling, an instinct or following some vague hand wavy rule of thumb.
At best we use type theory for type correctness and complexity theory to calculate efficiency. That's basically as far as it goes with "theory" and these two things aren't even about "software design".
Software design in practice as most engineers use it today is, practically speaking (key phrase), 100% art. Sometimes people come up with big fancy words like "dependency injection" or stupid Acronyms like SOLID to create the illusion of formal theory, but these things are nothing of the sort. It's just tips and tricks.
The plane, the car, the bridge? Those things use both design and formal theory... software design as most engineers use it, again, does not use ANY formal theory, it's almost just purely design all the way down.
Aren't you being overly optimistic about the engineering disciplines' ability to compute things? How does engineering work: do you sit down with a spec (say, "create a wing that can lift a passenger plane"), and then run some formulas, and end up with a wing? Or do you propose a wing, based on past experience (rough shape and size), and _then_ bring in computation to make sure it provides the correct amount of lift, iterating through designs as you go?
Because I think it's really the last one. There is no formula to design a bridge: you design the bridge, and then use formulas and lookup tables to validate it is strong enough. Same for pretty much anything else produced by any engineering discipline.
So in that sense, engineering and programming aren't all that far apart: both start from past experience, and use various validation methods after a design has been proposed, iterating through designs to reach an optimal state. Software engineering, being a younger discipline, is still working on validation methods, and many practitioners find they simply have no budget to apply them (nor any life-or-death constraints that force them to). That's ok though. If you design a new can opener you aren't going through all the processes that apply to an airliner either.
No. theory is very much part of the creation of the bridge. It is not just for verification.
If you read more carefully. What I am saying is that in software engineering, there is no theory. It's all Design. All made up. There's also no verification of the design itself.
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Just because it doesn't use formal theory now --- does not mean it/we shouldn't use it. I'm talking about needs, not haves.
Well in all other engineering fields although they are used in conjunction. The two concepts are practically more or less mutually exclusive. There's no room for "design" when finding the shortest distance between two points because the shortest distance between two points is done via calculation using formal theory.
Things like user-friendliness can be "philosophical". You can separately and selectively apply theory and design where applicable, but they cannot in actuality be unionized in some unholy grafting.
I would say for the topic at hand; Of how to organize and abstract your code, if we ever find a complete formal theory for that, much of design will go out the window and what's left is mostly a calculation.
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Mathematics and science can both be viewed as very fleshed out and practical branches philosophy, so they certainly aren't mutually exclusive.
Everything on the face of the earth falls under philosophy. It's the biggest non-category ever.
I'm basically talking about "philosophy" the way the book uses the word. Which in short is just the authors opinionated take on software masquerading as something a bit more "official" then just an opinion. I mean would you call your own opinions on software design a "philosophy"?
Yes probably. The only real difference between an opinion and a philosophy are the number of people that believe it.
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