David Chisnall takes a look at the two dominant paradigms in object-oriented languages (classes and prototypes) and discusses the strengths and weaknesses of each.Two terms are quite often confused when describing programming languages:class-based and object-oriented:Simula was the first class-based language. It provided classes (actually implemented using closures) as a means of encapsulating abstract data types.Smalltalk was the first object-oriented language. It provided a mechanism for decomposing programs into subprograms that ran on a simplified model of a computer an...

This week, I talked with Dan Russell, a search anthropologist at Google, about the time he spends with random people studying how they search for stuff. One statistic blew my mind. 90 percent of people in their studies don't know how to use CTRL/Command + F to find a word in a document or web page! I probably use that trick 20 times per day and yet the vast majority of people don't use it at all."90 percent of the US Internet population does not know that. This is on a sample size of thousands," Russell said. "I do these field studies and I can't tell you how many hours I've sat in somebo...

I've surprised myself and made another career change. I had a great time at Google, met lots of interesting people, but I met some folks outside doing something completely outrageous, and after much anguish decided to leave Google.I'm now at a small startup called Liquid Robotics They have a growing fleet of autonomous vehicles that rove the ocean collecting data from a variety of onboard sensors and uploading it to the cloud. The robots have a pile of satellite uplink/GSM/WiMax communication gear and redundant GPS units. They have a bunch of deployments. For example, one is a set of...

How do you answer the question, “what do I need to learn to be a good programmer?” I have written posts trying to answer that question, typically focusing on the languages that you should learn or the algorithms and other techniques you need to know. What about the rest of a programmer’s life? This is a less serious look at the life of a programmer. So, what does a programmer really need to know?Caffeine â€“ You need to find your preferred caffeine delivery system. Mine is black coffee, early and often. Others may prefer diet soda throughout the day. There are alwa...

I got an email request to publish this article a few days ago.I was actually on the verge of moving the email to the trash when I noticed the first name of the author: Rand.For those of you not familiar with the Wheel of Time series, the main character’s name is Rand.I admit that it’s an embarrassing weak reason to respond to a strange email, but reading some 10,000 pages of a fantasy series obviously messes with your mind.Then again, it’s probably no stranger than Rand Mendoza wanting to publish his article on this blog to begin with.Anyways, enjoy…**...

That’s the challenge.Sit down with someone you’ve never met and try to work out if they are a coder or a clown.I don’t mean to insult anyone, of course, and I’m the first to acknowledge the years of training and effort that goes into being a professional clown.But some coders, oh boy.Like the time I interviewed a recent graduate. I’ll call her Ada. Full of sympathy for the novice programmer I started with a gentle warm-up, a soft-ball question to break the ice.I asked Ada to write some code, on paper, that would print the word “hello” ten times. A...

Yesterday I gave a presentation at Xebia India office on MapReduce. It really went well and audience was able to understand the concept of MapReduce (as per their feedback). So, I was happy that I did a good job in explaining MapReduce concept to a technical audience (mainly Java programmer, some Flex programmer and few testers). After all the hard work and a great dinner at Xebia India office I reached back my home. My wife (Supriya) asked me “How was your session on …” , I replied it went well. So next she asked what was your session all about (she is not in softw...

I’ve taken and marked a lot of programming tests in the past. I love doing them as it’s always good to see what challenges different programmers have come up with when designing them. Unfortunately, however, most of them aren’t very good. Below is a list of general ideas to help increase the quality of programmer tests.1. Keep it relevantToo many of the tests have questions on content that simply isn’t relevant to the job. The whole idea behind a programming test is making sure the candidate is competent enough to fulfill the role. It shouldn’t be asking ques...