Strange behaviour of keywords within macros in Clojure
clojure, dictionary, keyword, macros
Solution
You should take into account that macro's don't evaluate their arguments, unless you tell them so. In your version, get-a gets a symbol m and the result isn't code, it is keyword :a looking itself up in a symbol, which is obviously nil. This works however:
(defmacro get-a [x] `(:a ~x))
The result of calling this macro with argument m is the expression '(:a m)', which evaluates to 1 in your context.
Problem
I'm a little confused by how keyword accesses seem to behave in Clojure when they are evaluated at macro expansion time. The following works as I expect: ``` (def m {:a 1}) (:a m) => 1 ``` However the same keyword access doesn't seem to work within a macro: ``` (def m {:a 1}) (defmacro get-a [x] (:a x)) (get-a m) => nil ``` Any idea what is going on here?