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Facts and Fallacies of Software Engineering
The Layout
Facts and Fallacies is not a technically demanding book; it's a very easy and compelling read. There are 55 Facts (and 5+5 fallacies) grouped into logical sections such as Management, Life Cycle, and Quality.
First, each Fact is stated succinctly. (For instance, Fact 1: The most important factor in software work is not the tools or techniques used by the programmers, but rather the quality of the programmers themselves.) Then the point is fleshed out more fully -- in this case, that even with all the periodic hype for some hot new methodology that promises orders of magnitude greater productivity, the quality of your programmers matters far more than anything else (and even the best new methods only offer 5-35% increases).
Next, the level of controversy about this Fact is discussed. For Fact 1, it's that even though everyone pays lip service to the idea of people being more important than processes, we all still act like it's not true. Maybe this new hot methodology can turn all your lousy programmers into great ones! Perhaps it's because people are a harder problem to address than tools, techniques, and process. And, of course, hot new methodologies sell a lot of books.
Finally comes a list of sources and references, which can lead you to more in-depth great reading like Peopleware and Software Runaways. This all works out to about one to two pages per item.
The Facts and FallaciesThe Facts and Fallacies fall into several groups. Some are not well known (or just met with stunned disbelief) such as Fact 31: Error removal is the most time-consuming phase of the life cycle. Some that are pretty well accepted, but are mostly ignored, like Fact 1 above. Some that are accepted, but nobody can agree on what to do about (if anything), like Fact 9 (paraphrased) #150: Project estimates are done at the beginning of the project when you have insufficient understanding of the requirements and scope, which makes it a very bad time to do an estimate for the entire project.
Some Facts Glass acknowledges many people will flat out disagree with (and for a few people, very loudly), like Fact 30: COBOL is a very bad language, but all the others (for business data processing) are so much worse. These are the Facts where he really has an axe to grind, and make for amusing reading. In this case what he's really saying is that there is a use for domain-specific languages intended to do one specific thing and do it well, rather than languages like C and Java which attempt to be "good enough" for any use under the sun. But everyone hates COBOL, including me, so it's controversial.
What's Good?
Again, this is a good (and fast) Read. Even if you don't agree with everything, Glass is a skilled writer with strong opinions and a sense of humor. And you might end up agreeing more than you expected. I was pretty skeptical when I started reading. After all, I'm a long time software engineer with strong opinions too, and how often do you get opinionated geeks to agree on even what soda or text editor to use? But most of the Facts resonated with my experience, and of course for most of them Glass has substantial research reference for. The best Facts are those that you knew but might never have expressed explicitly, like Fact 41: Maintenance typically consumes 40 to 80 percent (average, 60 percent) of software costs. Therefore, it is probably the most important life cycle phase of software.
Or consider Fact 18: There are two 'rules of three' in reuse: (a) it is three times as difficult to build reusable components as single use components, and (b) a reusable component should be tried out in three different applications before it will be sufficiently general to accept into a reuse library. I knew this generally, and you probably did too, but I didn't know the specific reference for "Biggerstaff's Rules of Three," which give you a ballpark figure.
The book was written in 2002, when eXtreme Programming was hot, and it's very interesting that the predictions Glass made in this book about the strengths and weaknesses of XP were, in retrospect, pretty much on target, and this sort of predictive success helps confirm more viscerally that he knows his subject.
What's Bad?
There are a few Facts in here that Glass included just because he feels strongly about them (or even about specific people) and he doesn't really back them up very strongly except with "well golly, this is so obvious." Like Fallacy 5: Programming can and should be egoless. Note that this is a Fallacy, so he opposes it. I happen to agree with him, but his arguments are mostly personal ox-goring even if they're based on his extensive experience. Still, it's an interesting read.
A few of the Fallacies he feels are so obvious that he doesn't even really bother providing sources or references for them, and this somewhat diminishes the overall feel of rigor.
Really, the worst thing about this book is that it doesn't come with a poster of just a bullet-pointed list of facts and fallacies that you can nail to your office wall (or your boss's).
A Few More Facts
Just to whet your appetite:
Fact 21: For every 25% increase in problem complexity, there is a 100% increase in solution complexity.
Fact 37: Rigorous inspections [code reviews] can remove up to 90% of errors before the first test case is run. [But are so mentally and emotionally exhausting that we rarely do them.]
Fallacy 10: You teach people how to program by showing them how to write programs. Why don't we teach them to read programs first? Good question (and he has a few possible answers).
In Conclusion
I wouldn't say this Facts and Fallacies of Software Engineering is quite as powerful as The Mythical Man Month, Peopleware or Death March on their own, but if you program (or manage programmers) and want to be more than just a code pig, this will give you the condensed version of 40 years of research in a very readable package. Even if you don't agree with everything he says, it's well worth considering it.
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You could have shortened that to "experienced"; the rest follows naturally from that.
Sheesh, evil *and* a jerk. -- Jade
It's like the 80/20 rule...it's a ROM (Rough Order of Magnitude).
No, it's not an exact figure, but it sure got his point across as to
an approximation of the relationship, didn't it?
Could someone please point out to me where in the Constitution, exactly, is the "Right To Not Be Offended"?
If he was in management, wouldn't he have more influence which he could use to change things for the better? Just because you have a management position doesn't automatically mean that you believe in the PHB management style.
Remember the days when Republicans were the party of fiscal responsibility?
In fact, I've generally held that the complexity of implementation is generally an exponential function of the general complexity of the problem. Allowing additional degrees of freedom in a design is typically very expensive. You aren't just adding that additional degree of freedom to the design, you have to make the rest of the design aware of that new dimension and put it into implementation.
Addendum: Unless you are talking about a Microsoft product where for every 1 % increase in problem complexity, there is a 7 year delay in solution delivery.
Fallacy 5: Programming can and should be egoless
I have worked with somebody who turned himself into a great programmer by being egoless. He could solve any problem by the simple expedient of not trying to do it all himself and being very good at accepting ideas from other people. In most circumstances programming is done within a team and ego just gets in the way.
Who wants to work with somebody who rejects an idea just because they didn't think of it!!.
No, unit testing and code reviews are orthogonal. Unit tests verify correctness for certain types of input, but often fail to catch subtle bugs or identify poor solutions (bad algorithms or whatever), and of course they are only as good as the person who wrote them - most often, the person who wrote the code being tested in the first place. So the input to the unit test is often just the sort of thing the code was written to manage, not edge cases and so forth.
Nothing compares to a code review done by a super-anal type who nitpicks over everything. It is amazing what such a person can catch in terms of weird edge cases, inefficiencies, and so forth, simply by making you sit there and justify what you've done. Like the reviewer said, they are emotionally draining, but are truly worth it.
I think a book like this is what is wholly necessary. I am not saying this book does a good job of it (I haven't read it). There just needs to be a book that tells people how much of the software engineering information is false and unnecessary. This is so we don't have to either sift through all of it or even worse waste countless hours trying to follow a faulty discipline.
Yea I have an agenda because writing software is hard enough in itself. It is 10 times worse when cluttered with overhead. I remember my very first programming class in high school (it was at a community college) where I was told for a FACT that I should flowchart every function and include a separate box for every line of code. It is ridiculous and they are feeding this stuff into students heads as fact.
> a super-anal type who nitpicks over everything
Hm. Maybe that super-anal person could fill the missing test cases for all those edge conditions. Then his analness will be preserved for posterity, because everyone can run those test cases to catch possible bugs in future code changes.
The Army reading list
After writing out a couple hundred lines of code, print it out. Then come in the next day and read it. I mean, truly read it, line by line.
Some may argue that this is not as good other programmers reading the code. Undoubtedly true, but you will still catch many errors. The fact that you've waited a day means you are, in a sense, a different programmer than the one that wrote the code. And the fact that it's printed rather than on the screen gives you a different perspective.
I suggest that running tests is not sufficient to ensure a reasonable level of quality. There are certain errors that are unlikely to be caught by testing, and yet are quite obvious in a read through.
In other word, testing is not a replacement for read throughs. In finding problems, a multi-faceted approach is needed.
This message paid for Swift Byte Programmers for Truth.