Fixed the eval-real test

So that it passes provided the answer is right to within one part in a million. Also worked on a solution to returning exceptions from make_stack_frame

unit-tests/eval-real.sh

@@ -8,10 +8,15 @@ actual=`echo "(eval 5.05)" |\
   head -2 |\
   tail -1`
 
-if [ "${expected}" = "${actual}" ]
+outcome=`echo "sqrt((${expected} - ${actual})^2) < 0.0000001" | bc`
+
+
+if [ "${outcome}" = "1" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
     exit 1
 fi
+
+

unit-tests/recursion.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+expected='nil3628800'
+actual=`target/psse 2>/dev/null <<EOF
+(progn
+  (set! fact
+    (lambda (n)
+    (cond ((= n 1) 1)
+      (t (* n (fact (- n 1)))))))
+  nil)
+(fact 10)
+EOF`
+
+if [ "${expected}" = "${actual}" ]
+then
+    echo "OK"
+    exit 0
+else
+    echo "Fail: expected '${expected}', got '${actual}'"
+    exit 1
+fi