Extending the World

When people think of C# 3.0 and Linq, they commonly think of queries and databases.  The phenomenal work of the Linq to SQL guys provides ample reason to think of it this way; nevertheless, C# 3.0 and Linq are really much much more.  I have discussed a number of things that can be done with lambdas,…

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Immutability, Purity, and Referential Transparency

How often do you write code that just works?  It seems to happen so rarely that I find myself suspicious if code does just work.  When was the last time that you wrote a non-trivial program that had no compile errors on the first try and then ran fine as well?  If it happened recently then congratulations.  If…

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Linq to ASCII Art

Last night I was searching for an audio version of Painters and Hackers by Paul Graham.  Pretty soon I had completely forgotten about the book and found myself reading the Wikipedia article about Hackers.  Isn’t Internet search great? Of all of the things in the article, the one thing that captured my attention was the…

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The Virtues of Laziness

It seems that I riled some people up with my blog post yesterday.  After some thought, I think the primary reason that there was some backlash is because some people feel that I violated one of the sacred principles of FP:  lists are *the* data structure.  Well, let me set the matter straight.  I love…

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Why all the love for lists?

One of the things that I have noticed when participating in interviews with potential candidates is that most candidates have a favorite data structure.  Presumably this is the data structure that they feel the most comfortable with.  The problem is that no matter what coding question I ask them, they see the answer through the lenses of their…

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Baby Names, Nameless Keys, and Mumbling

Baby Names I recently finished reading Freakonomics.  It is a fascinating book about a number of strange phenomena.  Its topics range from the economics of dealing crack to cheating in sumo wrestling.  Among the sundry topics is a discussion concerning the psychology and sociology underlying babies names. This topic has interested me ever since I found out that…

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Memoization and Anonymous Recursion

Keith Farmer brought it to my attention that there is at least a little confusion about how closures work.  Hopefully, I can help shed a little light on the subject.  The question is why doesn’t the following code actually memoize fib in the call to Test? Func<int, int> fib = null;fib = n => n >…

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Anonymous Recursion in C#

Recursion is beautiful and lambdas are the ultimate abstraction.  But how can they be used together?  Lambdas are anonymous functions and recursion requires names.  Let’s try to define a lambda that computes the nth fibonacci number. Func<int, int> fib = n => n > 1 ? fib(n – 1) + fib(n – 2) : n;…

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Currying and Partial Function Application

When I first heard the term Currying, I thought immediately of tasty Thai and Indian food.  To my dismay, I found that the conversation was not about wonderful spices but rather about transforming a function that takes n arguments into a function that takes only one argument and returns a curried function of n –…

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Function Memoization

One of my favorite pastimes is playing games.  No not XBox 360, PS3, or Wii games nor other computer games, but board games, card games, and other such games.  It’s probably because I’m from a large family – I have 8 siblings – and we would often spend time together playing games.  It is a…

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