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Anthropomorphism and Object Oriented Programming
An anonymous reader writes: We've all been warned about how anthropomorphizing animals and machines can lead us astray. But Edsger Dijkstra once cautioned (PDF) developers against thinking of their programs that way as well. "I think anthropomorphism is worst of all. I have now seen programs 'trying to do things,' 'wanting to do things,' 'believing things to be true,' 'knowing things' etc. Don't be so naive as to believe that this use of language is harmless. It invites the programmer to identify himself with the execution of the program and almost forces upon him the use of operational semantics." A new article fleshes out Dijkstra's statement, providing a good example of where an anthropomorphized analogy for Object Oriented Programming breaks down when you push it too far.
Dijkstra spends time building an analogy, then explains how it's flawed, and uses that to argue against 'anthropomorphizing'.
That's nice, and I certainly agree that the analogy can only go so far, but he was the one to build that analogy in the first place. This is not a valid argument against anthropomorphizing at all.
I do agree with the conclusion that anthropomorphising is not a reason to call OOP better than procedural.
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"I don't know how many of you have ever met Dijkstra, but you probably know that arrogance in computer science is measured in nano-Dijkstras"
Ya, sure. It is so much better to use the phrase: "The program contains a variable that stores your name", instead of: "The program knows your name". English, ect. all was not designed to work that way. Unless you want to take a week to describe a single program, it really helps to anthropomorphise it.
Troll is not a replacement for I disagree.
For me, I prefer OO programming (c++/java) to functional programming (C-lang), just due to encapsulation. I like having an object, with methods for its attributes, public/private methods, and such. Then having the objects interact in my program. It kinda makes sense to how I think.
However, I also think that if a team or individual programmer can release software that serves a useful purpose, and is maintainable, then those are the only things that matter. Which language, functional or object-oriented 'way' that was used to get there? Seems less important.
Uh, Linux geek since 1999.
OO isn't about anthropomorphism, it's about isolation and providing a clear API. If this was a large scale project with fifty people working on code that could move students, I don't want them implementing fifty different versions of move_student that will break whenever the Student or Classroom model changes.
I know it's trendy to hate on things that have been around a while, and OO indeed isn't the answer to everything, but it's still a useful way of keeping a complex program from getting out of control.
How can I believe you when you tell me what I don't want to hear?
One of the more stupid blog-level postings I've read. I use "blog-level" as an insult, btw. because blogs are generally a source of shallow thinking, because it just is too convenient to publish some thoughts. When it is more trouble, you're also forced to polish them more.
Firstly, to understand the difference between trying to do and "trying to do", read some Dennett. If correctly understood, anthropomorphisms like the attribution of intention to a non-intentional entity can be extremely helpful.
Secondly, not even his example is anywhere near what he's trying to explain. Yes, the analogy breaks down but it has nothing to do with the convulted reasoning he's applying. The cause for the analogy to break down is that there's no equivalent to walking to the classroom in his example. All of his code simply assigns a classroom number, without any equivalent of the walking part. As soon as you add that - magic ! - the analogy works again.
Assorted stuff I do sometimes: Lemuria.org
Just saying: It's not Dijkstra talking rubbish. Dijkstra is died 12 years ago. There is a handwritten article by Dijkstra which probably made sense in 1983 when it was written. In 1983 Dijkstra didn't know about C++. Stroustroup didn't know about C++ in 1983.
"The program doesn't know to check for" is in fact more accurate than "The program wasn't designed to check for". The second statement could mean that it wasn't designed to do something, but might do it anyway - what the program ACTUALLY does is left somewhat ambiguous (this is a technique lawyers will often use answering in court). In the first instance the statement makes it quite clear the program DOES NOT KNOW HOW to do what you are talking about.
You can shorten something so far for clarity, but if you go to far you end up with less clarity.
The "thinks" part at the end could go though, removing that does no harm to clarity.
The thing is, writing clearly is just plain hard - being able to use anthropomorphic kinds of terms helps make it simpler to add clarity to description at the cost of somewhat wordier sentences... kind of like how sometimes you make a program a little more verbose so that a different programmer coming across the code later can understand it.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
By the same token, now you have to implement pie.toast() and cake.toast() and lots of other useless and irrelevant methods, even though you're never ever going to use them, simply because they extend the isBakeable() interface.
Unnecessary, since the IsBakeable interface provides a default implementation of the toast() method that throws an exception if you attempt to toast something that is not toastable.
The real issue is why the IsBakeable interface has a toast() method in the first place...