fix x/for (had a dirty repl, my bad) and put an example in the README.

README.md

@@ -14,7 +14,6 @@ Add this dependency to your project:
 [net.cgrand/xforms "0.1.0-SNAPSHOT"]
 ```
 
-
 ```clj
 => (require '[net.cgrand.xforms :as x])
 ```
@@ -28,6 +27,15 @@ Add this dependency to your project:
              Execution time mean : 11,609631 µs
 ```
 
+`for` is the transducing cousin of `clojure.core/for`:
+
+```clj
+=> (quick-bench (reduce + (for [i (range 128) j (range i)] (* i j))))
+             Execution time mean : 514,932029 µs
+=> (quick-bench (transduce (x/for [i % j (range i)] (* i j)) + 0 (range 128)))
+             Execution time mean : 373,814060 µs
+```
+
 `by-key` and `reduce` are two new transducers. Here is an example usage:
 
 ```clj

src/net/cgrand/xforms.clj

@@ -17,7 +17,7 @@
                         :let `(let ~expr ~body)
                         :when `(if ~expr ~body ~acc)
                         :while `(if ~expr ~body (reduced ~acc))
-                        `(reduce (fn [~acc ~binding] ~body) ~acc ~expr))) 
+                        `(clj/reduce (fn [~acc ~binding] ~body) ~acc ~expr)))
           `(~rf ~acc ~body)
           (clj/partition 2 (rseq (vec seq-exprs))))]
     `(fn [~rf]