On Sat, Feb 5, 2011 at 1:01 AM, Alan <a...@malloys.org> wrote:
> That's not how macros work. They can only operate on the parameters
> they're passed, as symbols and lists.
Clojure macros can also see literal maps, sets, and vectors, not to
mention integers, strings, and the like. (Ever seen
"IllegalArgumentException: let requires a vector for its binding" or
similarly?)
user=> (defmacro foo [x] `(println ~x "was a" ~(type x)))
#'user/foo
user=> (def a 42)
#'user/a
user=> (foo [])
[] was a clojure.lang.PersistentVector
nil
user=> (foo #{})
#{} was a clojure.lang.PersistentHashSet
nil
user=> (foo {})
{} was a clojure.lang.PersistentArrayMap
nil
user=> (foo a)
42 was a clojure.lang.Symbol
nil
user=> (foo 42)
42 was a java.lang.Integer
nil
user=> (foo "bar")
bar was a java.lang.String
nil
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