Fix docstrings, declarations in iter-defun

* lisp/emacs-lisp/generator.el (iter-defun): Correctly propagate
docstrings and declarations to underlying function.

lisp/ChangeLog

@@ -1,3 +1,8 @@
+2015-03-03  Daniel Colascione  <dancol@dancol.org>
+
+	* emacs-lisp/generator.el (iter-defun): Correctly propagate
+	docstrings and declarations to underlying function.
+
 2015-03-02  Daniel Colascione  <dancol@dancol.org>
 
 	* emacs-lisp/generator.el: New file.

lisp/emacs-lisp/generator.el

@@ -674,10 +674,16 @@ encapsulates the state of a computation that produces a sequence
 of values.  Callers can retrieve each value using `iter-next'."
   (declare (indent defun))
   (cl-assert lexical-binding)
-  `(defun ,name ,arglist
-     ,(cps-generate-evaluator
-       `(cl-macrolet ((iter-yield (value) `(cps-internal-yield ,value)))
-          ,@body))))
+  (let (preamble)
+    (when (stringp (car body))
+      (push (pop body) preamble))
+    (when (eq (car-safe (car body)) 'declare)
+      (push (pop body) preamble))
+    `(defun ,name ,arglist
+       ,@(nreverse preamble)
+       ,(cps-generate-evaluator
+         `(cl-macrolet ((iter-yield (value) `(cps-internal-yield ,value)))
+            ,@body)))))
 
 (defmacro iter-lambda (arglist &rest body)
   "Return a lambda generator.