Tag Archives: Scheme

Via Grant Rettke over at Wisdom and Wonder I found these slides from a talk at LispNYC by John Cowan on September 13. As readers from my old blog will recall, R7RS will be split into a “small Scheme” and … Continue reading →

I really like Guile but one very annoying thing about it is that it doesn’t expand file paths. If you want to load a file outside the current directory you have to specify the complete path. Emacs has a very … Continue reading →

Boolean functions are very simple. If B = {FALSE, TRUE } then a Boolean function of n variables has domain Bn and range B; that is f: Bn → B. This limits the number of possible functions. For example, there … Continue reading →

Over at Harder, Better, Faster, Stronger, Steven Pigeon has a nice post on Huffman codes. He explains how Huffman codes operate and works through a pencil and paper example. Because he doesn’t give a real implementation and because the usual … Continue reading →

In a previous post, I talked about FIFO queues and gave an implementation. Now I want to talk about another type of queue: the priority queue. In these queues every element has a priority and elements are removed from the … Continue reading →

FIFO queues are a standard data structure that have many uses but they can be surprisingly difficult to get right. The standard implementation is an array with two pointers called front and rear. It’s the details of maintaining the pointers … Continue reading →