Random Hacks

High-Performance Haskell

Posted by Eric Kidd Mon, 22 Jan 2007 13:32:00 GMT

Yesterday, I was working on a Haskell program that read in megabytes of data, parsed it, and wrote a subset of the data back to standard output. At first it was pretty fast: 7 seconds for everything.

But then I made the mistake of parsing some floating point numbers, and printing them back out. My performance died: 120 seconds.

You can see similar problems at the Great Language Shootout. Haskell runs at 1/2th the speed of C for many benchmarks, then suddently drops to 1/20th for others.

Here’s what’s going on, and how to fix it.

(Many thanks to Don Stewart and the other folks on #haskell for helping me figure this out!)

Tags Haskell, Performance | 9 comments

13 Ways of Looking at a Ruby Symbol

Posted by Eric Kidd Sat, 20 Jan 2007 08:20:00 GMT

New Ruby programmers often ask, “What, exactly, is a symbol? And how does it differ from a string?” No one answer works for everybody, so–with apologies to Wallace Stevens–here are 13 ways of looking at a Ruby symbol.

Tags Ruby | 14 comments