Emmanuel CHANTREAU on 2009-12-03 13:03:02 +0100:
In my futur program, it use a lot of binary trees with strings (words) as leaf. There is just arround 1000 words and they will appear a lot of times. The program will possibly consume a lot of process and memory (it is a mathematics proover).
I began this program in C++ but haskell has a prety good speed and memory footprint and is easier. But I don't know if it worth to do this optimization: having a dictionary to translate string words in Int.
The answer depends on the automatic optimizations in GHC, because GHC could compare quickely two strings if it is the same object, so it depends if program generated by GHC have a dictionary (tree) of strings internaly. Someone knows this ?
I don't know of a library to intern strings, but it's not too hard to implement. I couldn't find the code I wrote to do this, but I looked around a bit and this is about what I remember doing: http://www.haskell.org/pipermail/haskell-cafe/2005-June/010335.html For the application I was using, interning strings did provide a significant reduction in memory, but for whatever reason didn't help with speed.