+
+(multiple-value-bind (result error)
+ (ignore-errors
+ (loop for i in '(1 2 3) collect i always (< i 4)))
+ (assert (null result))
+ (assert (typep error 'program-error)))
+(assert (equal
+ (loop for i in '(1 2 3) collect i into foo always (< i 4)
+ finally (return foo))
+ '(1 2 3)))
+(assert (equal
+ (loop for i in '(1 2 3) collect i into foo always (= i 4)
+ finally (return foo))
+ nil))
+(multiple-value-bind (result error)
+ (ignore-errors
+ (loop for i in '(1 2 3) always (< i 4) collect i))
+ (assert (null result))
+ (assert (typep error 'program-error)))
+(assert (equal
+ (loop for i in '(1 2 3) always (< i 4) collect i into foo
+ finally (return foo))
+ '(1 2 3)))
+(assert (equal
+ (loop for i in '(1 2 3) always (= i 4) collect i into foo
+ finally (return foo))
+ nil))
+(multiple-value-bind (result error)
+ (ignore-errors
+ (loop for i in '(1 2 3) thereis (= i 3) collect i))
+ (assert (null result))
+ (assert (typep error 'program-error)))
+
+(multiple-value-bind (result error)
+ (ignore-errors
+ (loop with i = 1 for x from 1 to 3 collect x into i))
+ (assert (null result))
+ (assert (typep error 'program-error)))
+(multiple-value-bind (result error)
+ ;; this one has a plausible interpretation in terms of LET*, but
+ ;; ANSI seems specifically to disallow it
+ (ignore-errors
+ (loop with i = 1 with i = (1+ i)
+ for x from 1 to 3
+ collect (+ x i)))
+ (assert (null result))
+ (assert (typep error 'program-error)))
+
+(let ((it 'z))
+ (assert (equal
+ ;; this one just seems weird. Nevertheless...
+ (loop for i in '(a b c d)
+ when i
+ collect it
+ and collect it)
+ '(a z b z c z d z))))
+
+(let ((ht (make-hash-table)))
+ (setf (gethash 1 ht) 3)
+ (setf (gethash 7 ht) 15)
+ (assert (= (loop for v fixnum being each hash-key in ht sum v) 8))
+ (assert (= (loop for v fixnum being each hash-value in ht sum v) 18))
+ #+#.(cl:if (cl:eq sb-ext:*evaluator-mode* :compile) '(and) '(or))
+ (assert (raises-error? (loop for v float being each hash-value in ht sum v)
+ type-error)))
+
+;; arithmetic indexes can be NIL or symbols.
+(assert (equal (loop for nil from 0 to 2 collect nil)
+ '(nil nil nil)))
+(assert (equal (loop for nil to 2 collect nil)
+ '(nil nil nil)))
+
+;; although allowed by the loop syntax definition in 6.2/LOOP,
+;; 6.1.2.1.1 says: "The variable var is bound to the value of form1 in
+;; the first iteration[...]"; since we can't bind (i j) to anything,
+;; we give a program error.
+(multiple-value-bind (function warnings-p failure-p)
+ (compile nil
+ `(lambda ()
+ (loop for (i j) from 4 to 6 collect nil)))
+ (assert failure-p))
+
+;; ...and another for indexes without FROM forms (these are treated
+;; differently by the loop code right now
+(multiple-value-bind (function warnings-p failure-p)
+ (compile nil
+ `(lambda ()
+ (loop for (i j) to 6 collect nil)))
+ (assert failure-p))
+
+(assert
+ (equal
+ (let ((x 2d0))
+ (loop for d of-type double-float from 0d0 to 10d0 by x collect d))
+ '(0d0 2d0 4d0 6d0 8d0 10d0)))
+(assert
+ (equal
+ (let ((x 2d0))
+ (loop for d of-type double-float downfrom 10d0 to 0d0 by x collect d))
+ '(10d0 8d0 6d0 4d0 2d0 0d0)))
+
+(let ((fn (handler-case
+ (compile nil '(lambda ()
+ (declare (special x y))
+ (loop thereis (pop x) thereis (pop y))))
+ (warning (c) (error "Warned: ~S" c)))))
+ (let ((x (list nil nil 1))
+ (y (list nil 2 nil)))
+ (declare (special x y))
+ (assert (= (funcall fn) 2))))
+
+;;; Incorrect LIST type declaration, reported and patched by Teemu
+;;; Kalvas: end testing is done "as if by atom" so this is supposed
+;;; to work.
+(assert (equal '(1 2) (loop for (a . b) on '(1 2 . 3) collect a)))
+
+;;; Detection of duplicate bindings, reported by Bruno Haible for CMUCL.
+(multiple-value-bind (_ condition)
+ (ignore-errors
+ (macroexpand '(LOOP WITH A = 0 FOR A DOWNFROM 10 TO 0 DO (PRINT A))))
+ (declare (ignore _))
+ (assert (typep condition 'program-error)))
+
+;;; Loop variable with a range excluding 0, reported by Andras Simon.
+;;; (Used to signal an error during macroexpansion.)
+(assert (not (loop with foo of-type (single-float 1.0 2.0) = 1.5 do (return))))