misc-code/test-of-iterators.lisp

;;;; test-of-iterators.lisp

(load "iterators.lisp")

(defpackage #:iterators-simple.tests
  (:use :cl
        :iterators-simple)
  (:export #:number-lines
           #:count-lines
           #:count-characters))

(in-package #:iterators-simple.tests)

;;; "test-of-iterators" goes here. Hacks and glory await!

(defun number-lines (file &optional (output-stream t))
  "Print each line prepended with its number."
  (let ((n 1)
        (get-line (create-iterator :stream file :line)))
    (flet ((get-line ()
             (call-iterator get-line)))
      (loop for line = (get-line)
         if (not line) do (return)
         else
         do (progn
              (format output-stream "~4d: ~a~%" n line)
              (incf n 1))))))

(defun number-of-lines (file)
  "Count the number of lines in a file."
  (let ((n 0)
        (get-line (create-iterator :stream file :line)))
    (flet ((get-line ()
             (call-iterator get-line)))
      (loop for line = (get-line)
         if (not line) do (return)
         else
         do (incf n 1))
      n)))

(defun count-characters (file)
  "This counts the number of characters in a file."
  (let ((n 0)
        (get-character (create-iterator :stream file :char)))
    (flet ((get-character ()
             (call-iterator get-character)))
      (loop for char = (get-character)
         if (not char) do (return)
         else
         do (incf n 1))
      n)))