Fawzi Mohamed:
> He also wrote a very nice book taken from his papers:
> Chris Okasaki
> Purely Functional Data Structures
> http://www.amazon.com/Purely-Functional-Structures-Chris-Okasaki/dp/0521663504/ref=sr_1_1?ie=UTF8&s=books&qid=1213262984&sr=8-1

Oh, you have found the book I was talking about here: http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D&article_id=72494 I think the author wants to write a new edition of that book soon.

Bye,
bearophile