+/* Joris van der Hoeven (he of TeXmacs fame) is a funny guy. He has his own
+ * ideas what a symbolic system should do. Let's make sure we won't disappoint
+ * him some day. Incidentally, this seems to always have worked. */
+static unsigned exam_joris()
+{
+ unsigned result = 0;
+ symbol x("x");
+
+ ex e = expand(pow(x, x-1) * x);
+ if (e != pow(x, x)) {
+ clog << "x^(x-1)*x did not expand to x^x. Please call Joris!" << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+/* Test Chris Dams' algebraic substitutions. */
+static unsigned exam_subs_algebraic()
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+
+ ex e = ex(x*x*x*y*y).subs(x*y==2, subs_options::subs_algebraic);
+ if (e != 4*x) {
+ clog << "(x^3*y^2).subs(x*y==2,subs_options::subs_algebraic) erroneously returned " << e << endl;
+ ++result;
+ }
+
+ e = ex(x*x*x*x*x).subs(x*x==y, subs_options::subs_algebraic);
+ if (e != y*y*x) {
+ clog << "x^5.subs(x^2==y,subs_options::subs_algebraic) erroneously returned " << e << endl;
+ ++result;
+ }
+
+ return result;
+}
+
+unsigned exam_misc()