;;; Commentary:

;; This is not really a test of calparse, but just some benchmarks on Guile's
;; built in SRFI-41 (stream) implementation. While running interactively the code
;; @lisp
;; (stream 1 2 3)
;; @end lisp
;; is extremely slow (0.5s). The problem however seems to go away during
;; compilation. Note however that
;; @lisp
;; (list->stream '(1 2 3))
;; @end lisp
;; is fast in both cases.

;;; Code:

(use-modules (srfi srfi-19)             ; Time
             (srfi srfi-41)             ; Streams
             (srfi srfi-64)             ; Tests
             (srfi srfi-71)             ; let-multiple
             (ice-9 format))

;;; TODO use statprof insteadd

(define (timed thunk)
  "Returns two values, @var{result} and @var{time ellapsed}."
 (let ((start-time (current-time time-process)))
   (let ((result (thunk)))
     (let ((end-time (current-time time-process)))
       (values result
               (time-difference end-time start-time))))))

(define-syntax-rule (with-printed-time port expr ...)
  (let ((result duration (timed (lambda () expr ...))))
    (format port "~6f :: ~a~%"
            (+ (time-second duration)
               (/ (time-nanosecond duration) 1e5))
            (quote expr ...))))

(with-printed-time #t (stream 1 2 3 4 5))
(with-printed-time #t (list->stream '(1 2 3 4 5)))
(with-printed-time #t (stream->list (list->stream '(1 2 3 4 5))))
(with-printed-time
 #t (stream-cons
     1 (stream-cons
        2 (stream-cons
           3 (stream-cons
              4 (stream-cons
                 5 stream-null))))))

(display (make-string 60 #\-)) (newline)

(eval-when (load)
  (with-printed-time #t (stream 1 2 3 4 5))
  (with-printed-time #t (list->stream '(1 2 3 4 5)))
  (with-printed-time #t (stream->list (list->stream '(1 2 3 4 5))))
  (with-printed-time
   #t (stream-cons
       1 (stream-cons
          2 (stream-cons
             3 (stream-cons
                4 (stream-cons
                   5 stream-null)))))))