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Comment by ohyes | Hacker News Reader

"Programming on the other hand... code is either 0% correct or 100% correct. Anything less than 100% correct is broken."

I don't think that's true. Anything less than 100% correct is incorrect, it isn't necessarily broken. How do I know my program is not broken? I run it. If it produces the answers I want, I can generally assume it is not broken (with a dose of skepticism).

If it is actually incorrect, it could still compile, run and/or produce useful answers (it would depend on the input). Almost all of my code has subtle bugs that I have had to iron out at one point or another.

I know, I know; What about space shuttle control systems or critical airplane frobnobdicators? Fine. Those aren't lossy and forgiving, but systems like that are few and far between. There is a large subset of programs that are also lossy and forgiving. (Which I assume the majority of us work on).

Were it really a binary reality, we would have much less software.

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I was talking in terms of transformations, such as the clone tool. Clone takes a set of pixels, applies some math, and gives you a new set of pixels that look a bit like what you want. After you've applied clone, you're done (although you might need to apply some finishing touches).

There is just no room for such tools in programming. You can't have a tool that applies some transformation to the code but leaves half of it in a broken state. That would be worse than useless. No, a tool has to be 100% correct or introduce errors that are caught by the compiler, otherwise it'll take longer to find and fix its mistakes than it would to apply the transformation manually. And it turns out that making such perfect tools is incredibly hard.

How do I know my program is not broken? I run it. If it produces the answers I want, I can generally assume it is not broken (with a dose of skepticism).

But notice how much effort is put into making sure code is correct. We have unit testing, integration testing, fuzz testing, static analysis, formal verification, ... Games studios pay scores of people to sit around playing games all day. This is not seen in any other creative art.

Vim and Emacs are 20+ years old and still popular. They're still around precisely because they're really good tools for transforming source code.

Not really. As much as I love vim and Visual Studio, I use them because there's nothing better.

I'd love something better (maybe someday I'll care so much that I'll sit down and write it myself).

Uh? I don't know about vim, but emacs doesn't even get syntax highlight right for most languages.

It's a great text editor, and I appreciate it as such, but it understands way too little of programming languages other than Lisp to deserve being called an IDE.

Emacs doesn't really come with out-of-the-box great support for most languages. Even for one language there are usually several alternative modes available, from which you have to choose. Even for Lisp you probably want to consider SLIME instead of the default.

Unfortunately not every popular language has a truly great mode available. And the whole mode-ecosystem feel like a pita (especially for newcomers), but at least you have a choice, which you don't have with most other editors/IDE-s.

But your talk about syntax highlighting is just unfair. I for example use a JavaScript mode written by Steve Yegge, which actually contains a full-blown JavaScript parser which pretty much ensures that under normal circumstances I don't make syntax errors. Oh... and it also has syntax highlighting :)

"But notice how much effort is put into making sure code is correct. We have unit testing, integration testing, fuzz testing, static analysis, formal verification, ... Games studios pay scores of people to sit around playing games all day. This is not seen in any other creative art."

You would have all of these things with or without a 'clone' tool that produces approximately correct code. As long as it produces code that is in some way human readable, can be debugged using standard (above) means, and doesn't make too many mistakes, it would be fine (no worse than me writing code, at least).

I think that your assumption that it would make a lot of mistakes and that they would be tedious and difficult to debug is just that, an assumption. It might be as simple as the programmer simply 'touching things up'. We haven't seen the tool, it doesn't exist, so arguing about what it would do is a moot point.

The pre-packaged refactorings in the Smalltalk Refactoring Browser are like this. There are checks to see if the refactoring is guaranteed to be correct, and if the refactoring runs, you can be very sure it is. The refactoring commands are even undo/redo-able.

> Anything less than 100% correct is incorrect, it isn't necessarily broken.

> run and/or produce useful answers (it would depend on the input)

The fact companies can and do sell broken products that generate wrong answers, lock-up or crash from time to time has no relation to the fact the products are broken.

An old joke said that IBM stood for "Inferior, but marketable"

You'll note, that isn't what I was arguing.

You can have code that is not 100% correct, it still runs and generates reasonable answers, without crashing, and is very useful. Even code that has been worked on for years still has subtle bugs lurking in it.

Take the Linux kernel. It has bugs in it. Somewhere, there is a bug! I'm 100% sure of this. Same with Windows, OSX.

A non-trivial piece of software with a bug is a tautology. We don't say that these products are broken, because then all software products would necessarily be broken.

Sure, in software development we are doing our damnedest to approximate correctness, but we never get there.

A tool that writes approximately correct code would be very useful.

How would it be useful to me, if I spent my time scrutinizing and debugging the code output by the tool?

I'm sorry, but this kind of inconsiderate, care-free attitude about bugs is an obstacle to me as a developer, to the brink of being downright offensive. Assuming of course we're writing code which is more complex than Hello World.

All I want, as a programmer, is a tool which aids me in reading, writing and manipulating code, without getting in the way. A clone feature is completely useless to me; a proper IDE has (or would have, actually) a library of code that I can choose from for my purposes, or perhaps would let me choose from my own snippets I've written in the past. Simply letting me drag a function to the point(s) in the code I'd like it to be called and then placing the necessary #include directives and/or the necessary compiler/linker options, and perhaps taking care of some parameters based on default values, a conceptually simple task, seems like science fiction to vim or emacs.

It's utterly stupid. The article is right on. We're wasting our time on syntax errors.

We don't appreciate our craft.

<sarcasm> In other words your code validates past computation and adds error correction code to all files you have to the HDD? After all if you don't do that then it will often produce buggy output and crash. (http://www.pcguide.com/ref/hdd/perf/qual/specRates-c.html) </sarcasm>

At best software running on commodity hardware works most of the time and acceptably broken really is good enough. Granted we want to minimize failures, but there is a wide range between good enough to be useful and perfect.

Yeah, that's why we don't have anyone fixing bugs encountered in software we use.

Please.

PS. Who cares about perfect? You can't have perfect, and that wasn't my point. Please reread.

PPS. I'm happy to see you're invalidating all the subject of my current work (carrier-grade systems) based on what's good enough on commodity systems. Extrapolating is bad.

PPPS. Sarcasm tags are so 17th century Protestant.

That mindset often results in over engineered crap.

I once wrote a program to parse a source code in ways that is provably limited. However, based on way the code was written it worked often enough to be extremely useful. Just because an approach can never cover all cases does not mean must be ignored.

Sniper bullets have tighter tolerances than the average bullet but this increase costs and becomes useless at high rates of fire. Suggesting all systems need to be as accurate as possible is ignorant.

PS: I have written and used plenty of code sitting on DoD computers and believe me it’s not all golden. Walk around the Pentagon and guess what Windows is sitting on the vast majority of peoples desks.

Again, you're extrapolating just to prove me wrong. I admit it may seem 'extreme' to some, but advanced tools aren't a threat to us. However, our current culture as programmers shows that we don't even trust other people's source code, let alone tools, to do our job. In this context of today, a tool that "writes code" (imperfect, of course) is not to be trusted any more than me, you, or our colleagues.

But do not downplay the importance of not producing, fixing, and avoiding bugs. It's just wrong.

There are basically two ways to write software you can either completely understand the problem and create a completely understood solution, or you can approximate a reasonable solution and then patch. Now when it’s possible the first approach is far better, unfortunately some of the worst systems where created when people tried to use the first approach when it was simply too complex for any one person to understand.

If you have ever copied a function changed the name and modified the code you are on the second path. Now plenty of people have gone down that path and know it’s likely to produce bugs, but as long as you have reasonable mitigation strategies it can still be a good idea. Building a tool that does similar things with larger sections of code would be dangerous, but with a little care it could still be useful.

In the early days of Fortran compilers they tended to be buggy so people would often money patch the output. http://en.wikipedia.org/wiki/Monkey_patch While error prone this was significantly faster than hand coding in assembler from the start. This died out with the invention of better compilers, but plenty of good software was written before then.

PS: I wish most software could be written using the first approach. I just don't think that's possible.

"How would it be useful to me, if I spent my time scrutinizing and debugging the code output by the tool?"

How would it be useful to me, if I spent my time scrutinizing and debugging code put out by myself?

I am going to do the scrutinizing and debugging either way!

How is my attitude about bugs carefree? They are everywhere. They are inevitable. That isn't carefree, those are the facts of life. You screw up, I screw up, Tom screws up. (I consider myself more of the paranoid camp wrt bugs, personally).

I agree that at a minimum an IDE has to do the things you listed.

If I had a tool that generated code pretty much as good as mine, that I could debug and ship, where would the loss be? The tool doesn't exist, and probably won't exist, but if it did, it would be awesome.

"How would it be useful to me, if I spent my time scrutinizing and debugging the code output by the tool?"

How would it be useful to me, if I spent my time scrutinizing and debugging code put out by myself? ------

Small point: I'd much rather debug errors I introduced than ones a program did. If I made the errors, they will have a familiarity about them - "oh, I always misspell that," or "I wasn't paying attention there." I can't predict how a program might get it wrong.

I'd much rather debug errors I didn't write myself, they are much easier to find. I find that code I wrote (often) scans the way I intended to write it, not the way I wrote it.

"How would it be useful to me, if I spent my time scrutinizing and debugging the code output by the tool?"

How would it be useful to me, if I spent my time scrutinizing and debugging code put out by myself?

To contrast those too, consider the familiarity you already possess with your code, as opposed to the code that was written by others.

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