user=> (where (and (> i (- 3 1)) (< i ~(+ 3 1))))
"where i > 3 - 1 and i < 4"
user=> (let [my-name "'chouser'"] (where (and (> id 0) (= name ~my-name))))
"where id > 0 and name = 'chouser'"

This 'where' macro produces something that looks vaguely like a SQL
"where" clause.  It accepts s-expressions to translate, but also
allows you to mark sub-expressions with ~ to indicate that they should
be evaluated as regular clojure expresions, and not translated
literally to SQL.  If it were more than a toy example, it would use
prepareStatement or similar to get appropriate quoting of clojure
objects, rather than just stuffing them directly in the resulting
string.

Here's the code:

(defmacro where [e]
  (let [f (fn f [e]
            (if-not (list? e)
              [(str e)]
              (let [[p & r] e]
                (if (= p `unquote)
                  r
                  (apply concat (interpose [(str " " p " ")]
                                           (map f r)))))))]
    (list* `str "where " (f e))))

--Chouser