Simplify loopy-let*.

loopy.el

@@ -981,16 +981,17 @@ you wish to use `pcase' destructuring, you should use `pcase-let'
 instead of this macro."
   (declare (debug ((&rest [sexp form]) body))
            (indent 1))
-  ;; Do this instead of using `pcase-let*' so that we error appropriately
-  ;; as expected.
-  (loopy (accum-opt all-found-vars all-exprs)
-         (list (var val) bindings)
-         (set (expr found-vars) (loopy--destructure-for-iteration-default var val))
-         (append all-found-vars found-vars)
-         (collect all-exprs expr)
-         (finally-return `(let ,(seq-uniq all-found-vars)
-                            ,@all-exprs
-                            ,@body))))
+  (let ((result (macroexp-progn body))
+        (errsym (gensym "loopy--value-capture")))
+    (pcase-dolist (`(,var ,val) (reverse bindings))
+      (setq result `(pcase ,val
+                      ((loopy ,var)
+                       ,result)
+                      (,errsym
+                       (signal 'loopy-bad-run-time-destructuring
+                               (list '(loopy ,var)
+                                     ,errsym))))))
+    result))
 
 ;;;###autoload
 (defmacro loopy-ref (bindings &rest body)