Closer is better

Overload resolution is of course the process of taking a bunch of things with the same name and figuring out which of them the user meant. Different languages use different heuristics to try to figure this out. A “heuristic” is just a fancy word for a guess, and I’ve often said that one of the design characteristics of C# is that it is not a “guess what the user meant” kind of language. So if C# is going to make guesses, at least the process by which it does so should be easily explainable to users. Continue reading

Um, no

Dear non-English-as-a-first-language-speaking phishing attackers, let me point out all the ways that I know that this is not actually from PayPal. (Oddly enough gmail did not flag this as phishing, despite having a PayPal logo embedded in it and a link to what is obviously a phishing site.)

Dear Costumer, [A costumer is someone who makes clothing for actors. You meant “customer”.]

We need more information from you [missing period]

We need your help resoving [resolving] an issue with your account. To give us to work together on this, [this phrase doesn’t make any sense] we’ve temporarily limited what you can do with your account untill [until] the issue is resolved.

We need a little bit [of] information about you to help confirm you [your] identity [missing period]

Note: Please note that in 50% of cases you will receive this e-mail in the spam box, [comma splice] it is because of the increased security emailing services you use. [No, it’s because you’re criminals.]

UPDATE: This is deliberate! How astonishingly devious. See this transcript of On The Media and this Microsoft Research paper.

How much bias is introduced by the remainder technique?

(This is a follow-up article to my post on generating random data that conforms to a given distribution; you might want to read it first.)

Here’s an interesting question I was pondering last week. The .NET base class library has a method Random.Next(int) which gives you a pseudo-random integer greater than or equal to zero, and less than the argument. By contrast, the rand() method in the standard C library returns a random integer between 0 and RAND_MAX, which is usually 32768. A common technique for generating random numbers in a particular range is to use the remainder operator:

int value = rand() % range;

However, this almost always introduces some bias that causes the distribution to stop being uniform. Do you see why?
Continue reading

Fighting blind

No technology today. I’m spending this week in San Francisco at Coverity head office and did not have time to get blog posts in the queue ahead of time. But here’s a question I got from my friend Peggy a few days ago:

I watched The Return of the King on TV again last night and was left wondering: how it is that Gollum manages to get the Ring away from Frodo when Frodo is invisible?

Well that’s an amazing coincidence as I was watching TROTK on DVD with my housemate at I suspect the same time, even given the time zone difference. Clearly we are connected by some mysterious fifth sense! Continue reading

ATBG: method type inference with multiple interfaces

Today on the Coverity Development Testing Blog‘s continuing series Ask The Bug Guys, I take a question from an “Eric L”, who is confused about one of the subtle rules of method type inference despite having written the rule himself. My colleague Jon takes a question from a beginner C programmer about memory allocation.

As always, if you have questions about a bug you’ve found in a C, C++, C# or Java program that you think would make a good episode of ATBG, please send your question along with a small reproducer of the problem to We cannot promise to answer every question or solve every problem, but we’ll take a selection of the best questions that we can answer and address them on the dev testing blog every couple of weeks.

What I did on my long weekend

I had a delightful and relaxing American Thanksgiving weekend where I did not think about programming languages hardly at all. My general plan for the weekend was to (1) roast a turkey to feed 19, (2) make soup from the bones, and (3) do jigsaw puzzles with friends while eating soup.

Missions accomplished: (As always, click for larger versions.)



Many thanks to my crew of helpful friends who did most of the work putting Aragorn together.

I roast a turkey every year; people often ask me how to make it come out well. The answer is simple:

1) Brine the turkey for 12+ hours in a clean, food-safe five-gallon bucket with eight litres of water, half a kilogram of salt and two bottles of the cheapest chardonnay you can find.

2) Carefully follow the instructions in the Joy of Cooking. That is, truss the bird, roast it upside down at 325F for the first half, then flip it to roast breast side up for the second half. This solves the problem of undercooked legs and overcooked breast. Increase the temperature at the end, and measure the temperature inside the thigh. I find that going all the way to 175F is unnecessary; I’ve never had a problem with undercooked legs after the thigh gets to the mid to high 160’s. I stuff the cavities with apples and have someone else make the bread stuffing separately.

Next time on FAIC: Back to C# with another look at the method type inference algorithm.