When geniuses like Neil Simon and Mike Nichols can't put their fingers on a problem, what hope is there for the rest of us?
So when you get stuck just know, there is no Dr. House for writing. At times we’re all Frank Burns.
They create too many possible exit points for a function. To write correct code, you really have to think about every possible code path through your function. Every time you call a function that can raise an exception and don't catch it on the spot, you create opportunities for surprise bugs caused by functions that terminated abruptly, leaving data in an inconsistent state, or other code paths that you didn't think about.
A better alternative is to have your functions return error values when things go wrong, and to deal with these explicitly, no matter how verbose it might be.
It is funny how people think that the important thing about exceptions is handling them. In a well-written application there's a ratio of ten to one, in my opinion, of try finally to try catch. In the finally, you protect yourself against the exceptions, but you don't actually handle them. ... because in a lot of cases, people don't care. They're not going to handle any of these exceptions. There's a bottom level exception handler around their message loop. That handler is just going to bring up a dialog that says what went wrong and continue. The programmers protect their code by writing try finally's everywhere, so they'll back out correctly if an exception occurs, but they're not actually interested in handling the exceptions. (quotes re-arranged for my emphasis)
The title of the [prior] article was a reference to a specific code snippet that I copied from a book, where the book's author claimed that the code he presented was “cleaner and more elegant”. I was pointing out that the code fragment was not only cleaner and more elegant, it was also wrong.
You can write correct exception-based programming.
Mind you, it's hard.
It's easy to write bad code, regardless of the error model.
It's hard to write good error-code-based code since you have to check every error code and think about what you should do when an error occurs.
It's really hard to write good exception-based code since you have to check every single line of code (indeed, every sub-expression) and think about what exceptions it might raise and how your code will react to it. (In C++ it's not quite so bad because C++ exceptions are raised only at specific points during execution. In C#, exceptions can be raised at any time.)
Metrics have a purpose and a place in organizations and teams. They cannot be used as a substitute for thinking. Nor can organizations think management by numbers is enough for effective software delivery. Organizations must be vigilant against the undesirable behaviors that emerge due to the inappropriate use of metrics.
Use the following guidelines to lead you to a more appropriate use of metrics:
1. Explicitly link metrics to goals
2. Favor tracking trends over absolute numbers
3. Use shorter tracking periods
4. Change metrics when they stop driving change
The most important factor in software work is not the tools and techniques used by the programmers, but rather the quality of the programmers themselves.
1. Some things need talent to do really well.
2. It's hard to scale talent.
3. One way people try to scale talent is by having the talent create rules for the untalented to follow.
4. The quality of the resulting product is very low.
What you really need are good players. Good players don't need a lot of rules.
(Or structure: “On the best teams, different individuals provide occasional leadership, taking charge in areas where they have particular strengths. No one is the permanent leader... The structure of the team is a network, not a hierarchy.” Peopleware: Productive Projects and Teams, 2nd ed., p. 155, Tom DeMarco and Timothy Lister -- via Dave Hoover's blog
[Non-agilists] see nothing -- or very little -- in the XP process definition that will make people successfully deliver -- but its true of any process. [They] want a process that will make others succeed. Agilists believe this view of process is inherently flawed. No process makes you successful, but people who will succeed anyway can do so with a more or less painful process.
XP is simply the best collection of practices I have ever found that are generally useful in addressing the problems I try to solve on each project -- but in the end, I succeed because of me and the people around me, not our process, which we readily change in response to our current challenges.
[W]e don't claim XP will protect us from the harmful, we claim that it aids the successful.
What do you consider the most important thing for a programmer to do when he begins working on a new project?
I think each should be sure they are in good physical condition without nagging psychological problems.
What do you consider the most important thing for a programmer to do when he begins working on a project that has already begun?
She should get sufficient information to decide, before signing on, whether she should sign on. Most programming projects that fail have already failed before most of the programmers have signed on, but through lack of courage or due diligence, many programmers sign on anyway. It's like doctors agreeing to do surgery on corpses.
Would you recommend a career in programming to young people today?
It depends on what the young person wants to do. I always give the same career recommendation: “Do what you want to do.”
What courses would you recommend they take? What languages/technologies should they key on?
They shouldn't key on languages and technologies. They should key on learning to communicate, to think, and to work well with other people. Once they have those, the languages and technologies become simple matters. Without them, no amount of language or technology expertise will do much good.
Take David Maxwell's bus ride. When he became CEO of Fannie Mae in 1981, the company was losing $1 million every business day, with $56 billion worth of mortgage loans under water.
Maxwell told his management team that there would only be seats on the bus for A-level people who were willing to put out A-plus effort. He interviewed every member of the team. He told them all the same thing: It was going to be a tough ride, a very demanding trip. If they didn't want to go, fine; just say so. Now's the time to get off the bus, he said. No questions asked, no recriminations. In all, 14 of 26 executives got off the bus. They were replaced by some of the best, smartest, and hardest-working executives in the world of finance.
With the right people on the bus, in the right seats, Maxwell then turned his full attention to the “what” question. He and his team took Fannie Mae from losing $1 million a day at the start of his tenure to earning $4 million a day at the end.
[O]nly a virtuous people are capable of freedom. As nations become corrupt and vicious, they have more need of masters.
Source: Benjamin Franklin, The Writings of Benjamin Franklin, Jared Sparks, editor (Boston: Tappan, Whittemore and Mason, 1840), Vol. X, p. 297, April 17, 1787.
found at http://www.wallbuilders.com/resources/search/detail.php?ResourceID=21
If I had to pick one as my key to software development it's that the critical element in a software development effort are the people you have doing the work. The productivity of the best developers is far more than the average, much more than the difference in salaries.He added another article in Feb 08 talking more about the productivity factor:
Although the technorati generally agree that talented programmers are more productive than the average, the impossibility of measurement means they cannot come up with an actual figure. So let's invent one for argument sake: 2. If you can find a factor-2 talented programmer for less than twice of the salary of an average programmer - then that programmer ends up being cheaper. To state this more generally: If the cost premium for a more productive developer is less than the higher productivity of that developer, then it's cheaper to hire the more expensive developer. The cheaper talent hypothesis is that the cost premium is indeed less, and thus it's cheaper to hire more productive developers even if they are more expensive.
People still trump process ... and theory, and ideas.
One of the great things I keep seeing (used to be “keep learning”, but at least by now I half expect it when things blow up in my face), is how the individual chemistry between people operates outside of all the nice theory we construct.
We get brilliant results from average people managing brilliant systems. Our competitors get average results from brilliant people working around broken systems. - Fujio Cho, Chairman Toyota MotorsElsewhere at Poppendieck's site, this paper gives more insight:
[Scholtes] says, “All of the empowered, motivated, teamed-up, self-directed, incentivized, accountable, reengineered, and reinvented people you can muster cannot compensate for a dysfunctional system....” So where does this leave us? Which is more important - process or people?
[The answer is both, “Process AND People”] ... People like to use effective processes, and they also like to have control over their own environment.... Process improvement may be done only “at the gemba” [the place of the problem] and it is up to the workers to decide whether or not a proposed improvement should be implemented.
Mistake No. 1: Start with a mediocre team of developers.
Designing software is hard, and unfortunately, a lot of the people who call themselves programmers can't really do it. But even though a bad team of developers tends to be the No. 1 cause of software project failures, you'd never know it from reading official postmortems.
At Fog Creek, we tend to review about 400 candidates for every full-time hire, because the best developers can be 10 times as productive as the merely excellent developers.
“Without excellent personnel, even good to excellent processes can only achieve marginal results.”
Maturity Models Have It Backwards
A mature person is one who is highly conscious of when it's appropriate to follow rules and when to break them. A mature person is largely self-guided. Only in exceptional circumstances does a mature person need to refer to or appeal to a rulebook at all.
“XP Requires High-Skill Teams”
This noxious notion burbles around the interwebs in various configurations, as it has since the beginning of XP. It’s mistaken.
I’ve worked with many more low-skill teams than high-skill ones, for two reasons:
I’m not cheap, therefore much of my business comes from teams that are in trouble. High-skill teams can hide and defer trouble far longer than low-skill ones.
There are far too few programmers, therefore the world of commerce has to settle for low-skill (and no-skill) ones. At least 75% of all programmers are low-skill ones.
I keep thinking I should give up before I start when I see a low-skill team. Fortunately, I am really bad at money, so I don’t refuse many clients. This has impressed upon me the complete irrelevance of skill level in adopting and adapting XP.
[Teams] should invest in one of the four values I want to talk about: skill. As someone who wants to remain anonymous said to me:I’ve also been tired for years of software people who seem embarrassed to admit that, at some point in the proceedings, someone competent has to write some damn code.
Here is a fact that will shock people who are unaware of the way computers and software are designed: at the extreme edges of the normal distribution, there are programmers who are 100 times more productive than the average programmer simply on the basis of the number of lines of computer code they can write in a given period of time. Going a bit further, since some programmers are so accomplished that their programming feats are beyond the ability of most of their peers, we might say that they are infinitely more productive for really creative, leading-edge projects.This makes me wonder how far back this notion of ‘X times more productive’ goes. 100x seems unlikely given any measure, but especially Cringely's measure of “lines of code.”
The trick to developing a new computer or program, then, is not to hire a lot of smart people but to hire a few very smart people. This rule lies at the heart of most successful ventures in the personal computer industry.
“We know that if you don't find it often, you often don't find it,” said [Lead researcher Jeremy Wolfe].In the NPR interview, the researcher went on to say even when doing the experiment on himself, with full knowledge of how many pictures in the stack of 2000 contain images with guns in them, he can't make his own accuracy increase. And any urgency brought to bear on the worker knowing what's at stake if something is missed does not seem to have any impact on their performance.
Rare stuff often gets missed. That means that if we look for 20 guns in a stack of 40 bags, we'll find more of them than if we look for the same 20 guns in a stack of 2,000 bags.
When you ask someone to perform a challenging task, without realizing it, their attention narrows and blocks out other things. So, often, they literally can't see even a huge, hairy gorilla that appears directly in front of them.
That effect is called “inattentional blindness.”
He took a picture of a man in a gorilla suit shaking his fist, and he superimposed that image on a series of slides that radiologists typically look at when they're searching for cancer. He then asked a bunch of radiologists to review the slides of lungs for cancerous nodules. He wanted to see if they would notice a gorilla the size of a matchbook glaring angrily at them from inside the slide.
But they didn't: 83 percent of the radiologists missed it, Drew says.