learning-suite test suite

((ran 3) (failed 0))

(define (test-alist-ref _)
  (let ((alst '((a 3) (b 2))))
    (⊦= '(3) (alist-ref 'a alst))
    (⊦= '(2) (alist-ref 'b alst))
    (⊦= #f (alist-ref 'c alst))))

(define (test/len _)
  (let ((my-strlen
          (foreign-lambda*
            int
            ((scheme-object cons))
            "C_return(C_header_size(cons));")))
    (⊦= 2 (my-strlen (cons 1 '())))
    (⊦= 2 (my-strlen (cons 1 (cons 2 (cons 3 '())))))
    (⊦= 11 (my-strlen "hello world"))))

(define (test-null-eq? _) (⊨ (eq? '() '())))