Fix a problem with $o being allowed in Exits leading to crash

Fixes #175141885 and is the second half of, and thus also fixes #18

compiler/stm.c

@@ -251,7 +251,8 @@ static void analyzePrint(Statement *stm, Context *context)
                     i++;
                     if (isdigit((int)buffer[i]))
                         parameter = buffer[i] - '0';
-                }
+                } else if (buffer[i] == 'o')
+                    parameter = 1;
             } else
                 parameter = buffer[i] - '0';
             if (parameter != 0)

compiler/testing/analyzePrintStatement.alan

@@ -1,7 +1,7 @@
 The l Isa location
     Exit w To l Does
       "We can'print a parameter like $1."
-      "But should also not allow $0."
+      "But should also not allow $o."
     End Exit.
 End The l.
 

compiler/testing/analyzePrintStatement.expected

@@ -0,0 +1,22 @@
+########## analyzePrintStatement ##########
+
+
+analyzePrintStatement.alan
+
+    3.        "We can'print a parameter like $1."
+=====>        1
+
+  *1*   551 E : String contains reference to a parameter that does not exist in
+                this context.
+
+    4.        "But should also not allow $o."
+=====>        1
+
+  *1*   551 E : String contains reference to a parameter that does not exist in
+                this context.
+
+
+        2 error(s).
+        No detected warnings.
+        1 informational message(s).
+