Data commit

Task/Arithmetic-evaluation/PicoLisp/arithmetic-evaluation-1.l

@@ -0,0 +1,23 @@
+(de ast (Str)
+   (let *L (str Str "")
+      (aggregate) ) )
+
+(de aggregate ()
+   (let X (product)
+      (while (member (car *L) '("+" "-"))
+         (setq X (list (intern (pop '*L)) X (product))) )
+      X ) )
+
+(de product ()
+   (let X (term)
+      (while (member (car *L) '("*" "/"))
+         (setq X (list (intern (pop '*L)) X (term))) )
+      X ) )
+
+(de term ()
+   (let X (pop '*L)
+      (cond
+         ((num? X) X)
+         ((= "+" X) (term))
+         ((= "-" X) (list '- (term)))
+         ((= "(" X) (prog1 (aggregate) (pop '*L)))) ) )

Task/Arithmetic-evaluation/PicoLisp/arithmetic-evaluation-2.l

@@ -0,0 +1,5 @@
+: (ast "1+2+3*-4/(1+2)")
+-> (+ (+ 1 2) (/ (* 3 (- 4)) (+ 1 2)))
+
+: (ast "(1+2+3)*-4/(1+2)")
+-> (/ (* (+ (+ 1 2) 3) (- 4)) (+ 1 2))