added more manual tests

sample-programs/basic-5

@@ -1,8 +1,8 @@
--- double : _Int -> _Int ;
--- double n = n + n;
+double : _Int -> _Int ;
+double n = n + n;
 
 id : 'a -> 'a ;
 id x = x ;
 
-main : ('a -> 'b -> 'c) ;
-main = id ;
+main : _Int ;
+main = id double 5;

sample-programs/basic-6

@@ -0,0 +1,10 @@
+data Bool () where {
+    True : Bool ()
+    False : Bool ()
+};
+
+main : Bool () -> _Int ;
+main b = case b of {
+    False => 0;
+    True => 0
+}

sample-programs/basic-7

@@ -0,0 +1,10 @@
+data Bool () where {
+    True : Bool ()
+    False : Bool ()
+};
+
+ifThenElse : Bool () -> 'a -> 'a -> 'a;
+ifThenElse b if else = case b of {
+        True => if;
+        False => else
+    }

sample-programs/basic-8

@@ -0,0 +1,24 @@
+data Maybe ('a) where {
+    Nothing : Maybe ('a)
+    Just : 'a -> Maybe ('a)
+};
+
+fromJust : Maybe ('a) -> 'a ;
+fromJust a =
+    case a of {
+        Just a => a
+    };
+
+fromMaybe : 'a -> Maybe ('a) -> 'a ;
+fromMaybe a b =
+    case b of {
+        Just a => a;
+        Nothing => a
+    };
+
+maybe : 'b -> ('a -> 'b) -> Maybe ('a) -> 'b;
+maybe b f ma =
+    case ma of {
+        Just a => f a;
+        Nothing => b
+    }