;;; -*- lexical-binding: t -*-
;;
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;; this file:
;;   https://dataswamp.org/~incal/peval/peval.el
;; -----------------------------------------------------------------------------

(load "peval")
(declare-function peval nil)

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(require 'benchmark)
(require 'calc-comb)
(require 'cl-lib)

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(defun peval--eform (&rest form)
  (format "%s" (eval (car form))))

;; (peval--eform (+ 1 3 3 7)) ; "14"

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(defun peval--primes-num (beg end &optional vrb)
  (cl-loop
   for i from beg to end
   count (= 1 (calcFunc-prime i)) into res
   if vrb finally do (message "%d" res)
   finally return res))

;; (peval--primes-num 1 99 t)

;; -----------------------------------------------------------------------------

(defun peval-test ()
  (let* ((beg 1)
         (end (expt 2 22))
         (crs 8)
         (prts `(,beg
                 ,@(butlast (cdr (mapcar #'floor (number-sequence beg end (/ (- end beg 0.0) crs)))))
                 ,end))
         (i 0)
         (del (make-string 37 ?\-))
         (peval-res 0)
         (peval-time
          (benchmark-elapse
            (mapc (lambda (s)
                    (if (numberp s)
                        (cl-incf peval-res s)
                      (when-let* ((_   (stringp s))
                                  (num (string-to-number s)))
                        (cl-incf peval-res num))))
                  (peval
                   `(peval--primes-num     ,(nth i prts)  ,(nth (cl-incf i) prts)) ; 1
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts)) ; 2
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts))
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts)) ; 4
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts))
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts))
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts))
                   `(peval--primes-num ,(1+ (nth i prts)) ,(nth (cl-incf i) prts)) ; 8
                   ))))
         (elisp-res)
         (elisp-time (benchmark-elapse (setf elisp-res (peval--primes-num beg end))))
         (optimal-time (/ elisp-time (* 1.0 num)))
         (optimal-perc (* 100 (/ optimal-time (* 1.0 peval-time)))))
    (cl-flet ((report (fun)
                (funcall fun (format "%s" del))
                (funcall fun (format "[problem size] 2**22 = %d" end))
                (funcall fun (format "[Emacs runnig] 1 + %d forked = %d" num (1+ num)))
                (funcall fun (format "%s" del))
                (funcall fun (format "[* plain done] %d %.4f s" elisp-res elisp-time))
                (funcall fun (format "[* peval done] %d %.4f s" peval-res peval-time))
                (funcall fun (format "[optimal deg.] %.1f percent" optimal-perc))))
      (if noninteractive
          (report #'message)
        (when-let* ((buf (get-buffer-create "*peval*"))
                    (_   (bufferp buf)))
          (with-current-buffer buf
            (erase-buffer)
            (report (lambda (s) (insert (format "%s\n" s))))
            (goto-char (point-min)))
          (pop-to-buffer buf))))))

;; (peval-test)

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(provide 'peval)

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