checkpoint

serde2/src/json/value.rs

@@ -0,0 +1,122 @@
+#[deriving(PartialEq)]
+pub enum Json {
+    Integer(int),
+    String(String),
+    Array(Vec<Json>),
+    Object(TreeMap<String, Json>),
+}
+
+pub struct JsonSerializer {
+    key: Option<String>
+}
+
+impl JsonSerializer {
+    pub fn new() -> JsonSerializer {
+        JsonSerializer {
+            key: None
+        }
+    }
+}
+
+impl VisitorState<Json> for JsonSerializer {
+    fn visit_int(&mut self, value: int) -> Json {
+        Integer(value)
+    }
+
+    fn visit_str(&mut self, value: &'static str) -> Json {
+        String(value.to_string())
+    }
+
+    fn visit_seq<
+        T: Serialize<JsonSerializer, Json>,
+        Iter: Iterator<T>
+    >(&mut self, mut iter: Iter) -> Json {
+        let (len, _) = iter.size_hint();
+        let mut v = Vec::with_capacity(len);
+
+        let mut first = true;
+        for elt in iter {
+            v.push(self.visit_seq_elt(first, elt));
+            first = false;
+        }
+
+        Array(v)
+    }
+
+    fn visit_seq_elt<
+        T: Serialize<JsonSerializer, Json>
+    >(&mut self, _first: bool, value: T) -> Json {
+        value.serialize(self)
+    }
+
+    fn visit_tuple<
+        V: Visitor<JsonSerializer, Json>
+    >(&mut self, mut visitor: V) -> Json {
+        let (len, _) = visitor.size_hint();
+        let mut v = Vec::with_capacity(len);
+
+        loop {
+            match visitor.visit(self) {
+                Some(value) => { v.push(value); }
+                None => { break; }
+            }
+        }
+
+        Array(v)
+    }
+
+    fn visit_tuple_struct<
+        V: Visitor<JsonSerializer, Json>
+    >(&mut self, _name: &'static str, visitor: V) -> Json {
+        self.visit_tuple(visitor)
+    }
+
+    fn visit_enum<
+        V: Visitor<JsonSerializer, Json>
+    >(&mut self, _name: &'static str, _variant: &'static str, visitor: V) -> Json {
+        self.visit_tuple(visitor)
+    }
+
+    fn visit_map<
+        K: Serialize<JsonSerializer, Json>,
+        V: Serialize<JsonSerializer, Json>,
+        Iter: Iterator<(K, V)>
+    >(&mut self, mut iter: Iter) -> Json {
+        let mut v = TreeMap::new();
+        let mut first = true;
+
+        for (key, value) in iter {
+            let value = self.visit_map_elt(first, key, value);
+            v.insert(self.key.take().unwrap(), value);
+            first = false;
+        }
+
+        Object(v)
+    }
+
+    fn visit_map_elt<
+        K: Serialize<JsonSerializer, Json>,
+        V: Serialize<JsonSerializer, Json>
+    >(&mut self, _first: bool, key: K, value: V) -> Json {
+        match key.serialize(self) {
+            String(key) => { self.key = Some(key); }
+            _ => { fail!() }
+        }
+        value.serialize(self)
+    }
+
+    fn visit_struct<
+        V: Visitor<JsonSerializer, Json>
+    >(&mut self, _name: &'static str, mut visitor: V) -> Json {
+        let mut v = TreeMap::new();
+
+        loop {
+            match visitor.visit(self) {
+                Some(value) => { v.insert(self.key.take().unwrap(), value); }
+                None => { break; }
+            }
+        }
+
+        Object(v)
+    }
+}