August, 2010: Some relational algebra with datatypes in Clojure 1.2

Clojure 1.2 has been released and Leiningen has moved up to 1.3.0 (or was it briefly 1.2.0) which supports the latest version - so I decided to spend a spare afternoon playing with one of the new features of Clojure.

One of the interesting new features is datatypes which are a replacement for the structmap feature from earlier versions of Clojure. Datatypes and structmaps are directly equivalent to maps. Clojure provides an implementation of relational algebra that works on its maps in the clojure.set namespace, I expected that these functions should work with datatypes but I decided to check for myself.

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