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Is abstraction overrated in programming? Chess, interviews and OOP

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Re: Is abstraction overrated in programming? Chess, interviews and OOP

#51

Post by fjsolwmv »

Silhouette wrote: post #25
Sinidir wrote: post #22

Earlier quoted context omitted.

Yeah during reading this i was wondering how someone can miss the point to that kind of degree. The point was to test for an understanding of object-oriented design. Yet he talks about how awesomely space effiencient his implmementation is compared to using objects. But the interviewers seemed to also miss the ball, making irrelevant and false objections.

It's a poor choice of scenario for an interview, because no-one who knew anything about writing chess software would ever write that sort of OO code. If the point was to test for an understanding of OO design, wouldn't it be a good idea to provide a problem where OO design was appropriate?

OO is for large problems, not 30-line whiteboard able problems. That's the challenge.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#52

Post by fjsolwmv »

alerighi wrote: post #20
johnfn wrote: post #13

The OP has translated the interviewers question of "design a readable and maintainable abstraction for a chessboard" into "design the most space-optimized chessboard possible", then wonders why the interviewer doesn't like his solution.

That is entirely subjective. I am more comfortable reasoning with bits than with object. I also think optimization matters, if you can reduce the memory consumption with a simple and elegant solution, why not ?

How would you build a GUI for your bits-based chessboard?

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#53

Post by valuearb »

“But first of all, the OO inheritance here is irrelevant. The queen is the only piece which actually “inherits” properties from other pieces! We don't need an object model to simply reuse some functions to calculate legal moves given a position. Just a few global functions.”

Don’t all pieces have a location? Aren’t all pieces movable? Might we want to display pieces? Do we want to journal them to files to save game state, or their moves to streams to play remotely?

All of these things can be done procedurally, but they also fit nicely into an OO design.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#54

Post by fjdfhdjldj »

valuearb wrote: post #53

“But first of all, the OO inheritance here is irrelevant. The queen is the only piece which actually “inherits” properties from other pieces! We don't need an object model to simply reuse some functions to calculate legal moves given a position. Just a few global functions.” Don’t all pieces have a location? Aren’t all pieces movable? Might we want to display pieces? Do we want to journal them to files to save game s…

but then why use OO? what does OO offer that this method does not? In fact one could argue that this method offers better decoupling since it separates the rendering from the game Data.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#55

Post by valuearb »

mnm1 wrote: post #31
johnfn wrote: post #13

The OP has translated the interviewers question of "design a readable and maintainable abstraction for a chessboard" into "design the most space-optimized chessboard possible", then wonders why the interviewer doesn't like his solution.

Oh please. As if the interviewer's next question wouldn't be "make it faster/more efficient" anyway. The interviewer is the problem here because he wants to build a chess game in an extremely stupid way using OOP for no other reason than to use OOP. I'd say most applications of OOP fail in similar ways in real life, creating monsters of complexity where simplicity could have existed. The author should consider himsel…

The interviewer gave the OP a simple question that could be answered within a short time to gauge how well they understood OO design, and OP specifically implemented it in a way to frustrate them. So again, whose the idiot?

If OP wanted to crush the question, they could quickly answer it by saying this is how you could implement using classes and inheritance, now let me explain why OO is a poor solution for this specific problem, and what kind of problem sets OO design is most useful in.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#56

Post by jstimpfle »

valuearb wrote: post #53

“But first of all, the OO inheritance here is irrelevant. The queen is the only piece which actually “inherits” properties from other pieces! We don't need an object model to simply reuse some functions to calculate legal moves given a position. Just a few global functions.” Don’t all pieces have a location? Aren’t all pieces movable? Might we want to display pieces? Do we want to journal them to files to save game s…

> Don’t all pieces have a location?

Make a table containing locations for each piece.

> Aren’t all pieces movable?

Make a function ("procedure") that moves a piece (e.g. edits the location table).

> Might we want to display pieces?

Make a render function (e.g. gets a piece type and a position)

> Do we want to journal them to files to save game state, or their moves to streams to play remotely?

Write serialization and deserialization routines (again, procedures that get piece type and position).

No need to cram that in to some idea of piece "class". That only glues things together that don't belong together. OO is pretty much crap.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#57

Post by valuearb »

fjdfhdjldj wrote: post #54
valuearb wrote: post #53

“But first of all, the OO inheritance here is irrelevant. The queen is the only piece which actually “inherits” properties from other pieces! We don't need an object model to simply reuse some functions to calculate legal moves given a position. Just a few global functions.” Don’t all pieces have a location? Aren’t all pieces movable? Might we want to display pieces? Do we want to journal them to files to save game s…

but then why use OO? what does OO offer that this method does not? In fact one could argue that this method offers better decoupling since it separates the rendering from the game Data.

You use OO because your interviewer wants an example that demonstrates you understand it.

Secondly, OO is more easily extensible. If the company wants the game to support other size boards, bit wise storage has to be ripped out. 90% of the work in 90% of the jobs is writing clear, easily maintainable and extensible code, not maximizing performance. Frankly, if I interview someone who answers a question like OP, i pass thinking their code will be a premature optimization nightmares.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#58

Post by fjdfhdjldj »

inopinatus wrote: post #49
Chriky wrote: post #32

Is this for real? The solution he proposes is specific to Chess ! I mean, does this guy really think the company cares about efficiently representing chess game states?? Obviously, obviously, OBVIOUSLY, the Chess aspects of this question are irrelevant. What they are trying to find out if how well you will work on their actual codebase, which is presumably not comprised of global functions operating on bitfields

The guy is openly arguing with an interviewer after taking a question too literally. I suspect my interview impressions would've included "candidate may be on the spectrum". However, this entire thesis is founded on a false dilemma, because you can write an OO domain model with a compact representation.

why the onus is not on the interviewer? Why is he bringing up chess if he just wants OO answers? Aren't there better problems to pose more suited for testing OO knowledge? Bitboard is a standard way of writing chess engines. I think most would agree that a good programmer is one that seeks the best solution, not one that follows dogmatically his preconceived ideas.

Re: Is abstraction overrated in programming? Chess, interviews and OOP

#60

Post by christophilus »

valuearb wrote: post #57
fjdfhdjldj wrote: post #54

Earlier quoted context omitted.

but then why use OO? what does OO offer that this method does not? In fact one could argue that this method offers better decoupling since it separates the rendering from the game Data.

You use OO because your interviewer wants an example that demonstrates you understand it. Secondly, OO is more easily extensible. If the company wants the game to support other size boards, bit wise storage has to be ripped out. 90% of the work in 90% of the jobs is writing clear, easily maintainable and extensible code, not maximizing performance. Frankly, if I interview someone who answers a question like OP, i pas…

Except, this is not premature optimization. Chess programs are a domain the author is familiar with. He goes out of his way to explain why-- based on his experience-- chess code should be written with space-optimization in mind.

Secondly, if you want to support non-standard boards, his solution requires a small tweak (depending on the language): long -> bigint and some parameter to denote board size.

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