Improve tests; Clean up

examples/async_download.ds

@@ -1,11 +1,20 @@
-cast = download("https://api.sampleapis.com/futurama/cast")
-characters = download("https://api.sampleapis.com/futurama/characters")	
-episodes = download("https://api.sampleapis.com/futurama/episodes")
+cast_len = 0
+characters_len = 0
+episodes_len = 0
 
 async {	
-	cast_len = length(from_json(cast))
-	characters_len = length(from_json(characters))
-	episodes_len = length(from_json(episodes))
+	{
+		cast = download("https://api.sampleapis.com/futurama/cast")
+		cast_len = length(from_json(cast))		
+	}
+	{
+		characters = download("https://api.sampleapis.com/futurama/characters")	
+		characters_len = length(from_json(characters))
+	}
+	{
+		episodes = download("https://api.sampleapis.com/futurama/episodes")
+		episodes_len = length(from_json(episodes))
+	}
 }
 
 output ([cast_len, characters_len, episodes_len])

examples/threads.ds

@@ -1,3 +0,0 @@
-handle = thread:spawn("my_thread", {
-	
-})

tests/value.rs

@@ -13,11 +13,29 @@ fn integer() {
     assert_eq!(interpret("-666"), Ok(Value::Integer(-666)));
 }
 
+#[test]
+fn integer_overflow() {
+    assert_eq!(
+        interpret("9223372036854775807 + 1"),
+        Ok(Value::Integer(i64::MIN))
+    );
+    assert_eq!(
+        interpret("-9223372036854775808 - 1"),
+        Ok(Value::Integer(i64::MAX))
+    );
+}
+
 #[test]
 fn float() {
     assert_eq!(interpret("0.1"), Ok(Value::Float(0.1)));
-    assert_eq!(interpret("12.3"), Ok(Value::Float(12.3)));
-    assert_eq!(interpret("-6.66"), Ok(Value::Float(-6.66)));
+    assert_eq!(
+        interpret("1.7976931348623157e308f64"),
+        Ok(Value::Float(f64::MAX))
+    );
+    assert_eq!(
+        interpret("-1.7976931348623157e308f64"),
+        Ok(Value::Float(f64::MIN))
+    );
 }
 
 #[test]