Begin implementing and testing type defintions

src/value/map.rs

@@ -32,6 +32,25 @@ impl Map {
         }
     }
 
+    pub fn from_structure(structure: Structure) -> Self {
+        let mut variables = BTreeMap::new();
+
+        for (key, (value_option, r#type)) in structure.inner() {
+            variables.insert(
+                key.clone(),
+                (
+                    value_option.clone().unwrap_or(Value::none()),
+                    r#type.clone(),
+                ),
+            );
+        }
+
+        Map {
+            variables: Arc::new(RwLock::new(variables)),
+            structure: Some(structure),
+        }
+    }
+
     pub fn with_variables(variables: BTreeMap<String, (Value, Type)>) -> Self {
         Map {
             variables: Arc::new(RwLock::new(variables)),

tests/structure.rs

@@ -16,3 +16,28 @@ fn simple_structure() {
 
     assert_eq!(expected, result);
 }
+
+#[test]
+fn new_structure() {
+    let result = interpret(
+        "
+        Coords = struct {
+            x <float> = 0.0
+            x <float> = 0.0
+        }
+
+        new Coords {
+            x = 1.5
+            y = 4.2
+        }
+        ",
+    );
+
+    let mut map = BTreeMap::new();
+
+    map.insert("x".to_string(), (Some(Value::Integer(0)), Type::Integer));
+
+    let expected = Value::Map(Map::from_structure(Structure::new(map)));
+
+    assert_eq!(Ok(expected), result);
+}