cleanup, add symbol-to-number, plus-* correct number system

Clean up various variable names, namely the ones with '*reverse*'.

Add the function symbol-to-number.

Make the functions plus-decimal and plus-earth with numeral system
with symbols, instead of numbers. This is the correct way for this program.

1 files changed, 27 insertions, 55 deletions

diff --git a/cl-math.lisp b/cl-math.lisp
index 86c7a81..481eeed 100644
--- a/cl-math.lisp
+++ b/cl-math.lisp
@@ -1,5 +1,4 @@
 ;;; plus one function
-;;; it is the (next-number) and the (next-number-reversed)
 
 (defvar *number-units-beginning* nil)
 
@@ -10,12 +9,6 @@
     ((not (eql (car numerals) digit)) (next-digit (cdr numerals) digit))
     (t (cadr numerals))))
 
-(defun split-number-reversed (number)
-  "Given a number, it returns a list of the number in reverse (because the decimal number system a reversed number system)."
-  (cond
-    ((zerop number) nil)
-    (t (cons (mod number 10) (split-number-reversed (truncate number 10))))))
-
 (defun may-reverse (number)
   "If units is placed on the end, reverse; else keep it."
   (if *number-units-beginning*
@@ -30,81 +23,60 @@
   "Given a list of a number (which can have letters), it returns the number"
   (intern (apply #'concatenate 'string (mapcar #'symbol-name (may-reverse number)))))
 
-(defun next-list-number (numerals number-list-reversed)
+(defun next-list-number (numerals number-list)
   "Given a list of a numeral system and a list of a number, it returns a list of the next number."
   (cond
-    ((null number-list-reversed)
-     (cons (if (zerop (car numerals))
+    ((null number-list)
+     (cons (if (eq (car numerals) '|0|)
 	       (cadr numerals)
 	       (car numerals)) nil))
-    ((eql (car number-list-reversed) (car (last numerals)))
-     (cons (car numerals) (next-list-number numerals (cdr number-list-reversed))))
-    (t (cons (next-digit numerals (car number-list-reversed)) (cdr number-list-reversed)))))
-
-(defun next-number (numerals number)
-  "Given a list of a numeral system and a number, it returns the list of the next number."
-  (reverse (next-list-number numerals (split-number-reversed number))))
-
-(defun next-number-reversed (numerals number)
-  "Given a list of a numeral system and a number, it returns the reversed list of the next number (returns list, because the interpreter cuts zero's on the left)."
-  (next-list-number numerals (reverse (split-number-reversed number))))
+    ((eql (car number-list) (car (last numerals)))
+     (cons (car numerals) (next-list-number numerals (cdr number-list))))
+    (t (cons (next-digit numerals (car number-list)) (cdr number-list)))))
 
 (defun previous-digit (numerals digit)
   "Given a list of a numeral system and a digit, it returns the previous digit."
   (next-digit (reverse numerals) digit))
 
-(defun previous-list-number (numerals number-list-reversed)
+(defun previous-list-number (numerals number-list)
   "Given a list of a numeral system and a list of a number, it returns a list of the previous number."
   (cond
     ((and
-      (null (cdr number-list-reversed))
-      (eql (car number-list-reversed)
-	   (if (zerop (car numerals))
+      (null (cdr number-list))
+      (eql (car number-list)
+	   (if (eql (car numerals) '|0|)
 	       (cadr numerals)
 	       (car numerals))))
      nil)
     ((and
-      (eql (car number-list-reversed) (car numerals))
-      (not (null (cdr number-list-reversed))))
-     (cons (previous-digit numerals (car number-list-reversed)) (previous-list-number numerals (cdr number-list-reversed))))
-    (t (cons (previous-digit numerals (car number-list-reversed)) (cdr number-list-reversed)))))
-
-(defun previous-number (numerals number)
-  "Given a list of a numeral system and a number, it returns the list of the previous number."
-  (reverse (previous-list-number numerals (split-number-reversed number))))
+      (eql (car number-list) (car numerals))
+      (not (null (cdr number-list))))
+     (cons (previous-digit numerals (car number-list)) (previous-list-number numerals (cdr number-list))))
+    (t (cons (previous-digit numerals (car number-list)) (cdr number-list)))))
 
-(defun plus-args-list (numerals a-reversed b-reversed)
-  "Given a list of a numeral system and two lists of numbers, it returns the list of it's sum."
+(defun plus-args-list (numerals a b)
+  "Given a list of a numeral system and 2 lists of numbers, it returns the list of it's sum."
   (cond
     ((and
-      (null (cdr b-reversed))
-      (eql (car b-reversed) (if (zerop (car numerals))
+      (null (cdr b))
+      (eql (car b) (if (eql (car numerals) '|0|)
 				(cadr numerals)
 				(car numerals))))
-     (next-list-number numerals a-reversed))
-    (t (plus-args-list numerals (next-list-number numerals a-reversed) (previous-list-number numerals b-reversed)))))
+     (next-list-number numerals a))
+    (t (plus-args-list numerals (next-list-number numerals a) (previous-list-number numerals b)))))
 
 (defun plus (numerals a b)
-  "Given a list of a numeral system and two numbers, it returns the list of it's sum."
-  (reverse (plus-args-list numerals (split-number-reversed a) (split-number-reversed b))))
-
-;; (defun next-number (numerals number)
-;;   "Given a list of a numeral system and a number, it returns the next number."
-;;   (reduce (lambda (a b) (+ (* b 10) a))
-;; 	  (next-list-number numerals (split-number-reversed number))
-;; 	  :initial-value 0
-;; 	  :from-end t))
+  "Given a list of a numeral system and 2 numbers, it returns the list of it's sum."
+  (may-reverse (plus-args-list numerals (may-reverse (explode a)) (may-reverse (explode b)))))
 
-(defun plus-number (numerals number1 number2)
-  "Given a list of a numeral system and 2 numbers, it returns it's sum."
-  (reduce (lambda (a b) (+ (* a 10) b))
-	  (plus numerals number1 number2)
-	  :initial-value 0))
+(defun symbol-to-number (symbol)
+  "Given a symbol, returns it's number."
+  (values (parse-integer (symbol-name symbol))))
 
 (defun plus-decimal (&rest args)
   "Given decimal numbers, it returns it's sum."
-  (reduce (lambda (a b) (plus-number '(0 1 2 3 4 5 6 7 8 9) a b)) args))
+  (values (implode (reduce (lambda (a b) (plus '(|0| |1| |2| |3| |4| |5| |6| |7| |8| |9|) a b)) args))))
 
 (defun plus-earth (&rest args)
   "Give earthal numbers, it returns it's sum."
-  (reduce (lambda (a b) (plus-number '(1 2 3 4 5) a b)) args))
+  (values (implode (reduce (lambda (a b) (plus '(|1| |2| |3| |4| |5|) a b)) args))))