1 files changed, 156 insertions, 0 deletions
diff --git a/src/index.rs b/src/index.rs
new file mode 100644
index 0000000..276db79
--- /dev/null
+++ b/src/index.rs
@@ -0,0 +1,156 @@
+use std::ops;
+
+use crate::document::Document;
+use crate::key::Key;
+use crate::table::TableKeyValue;
+use crate::{value, InlineTable, InternalString, Item, Table, Value};
+
+// copied from
+// https://github.com/serde-rs/json/blob/master/src/value/index.rs
+
+pub trait Index: crate::private::Sealed {
+    #[doc(hidden)]
+    fn index<'v>(&self, val: &'v Item) -> Option<&'v Item>;
+    #[doc(hidden)]
+    fn index_mut<'v>(&self, val: &'v mut Item) -> Option<&'v mut Item>;
+}
+
+impl Index for usize {
+    fn index<'v>(&self, v: &'v Item) -> Option<&'v Item> {
+        match *v {
+            Item::ArrayOfTables(ref aot) => aot.values.get(*self),
+            Item::Value(ref a) if a.is_array() => a.as_array().and_then(|a| a.values.get(*self)),
+            _ => None,
+        }
+    }
+    fn index_mut<'v>(&self, v: &'v mut Item) -> Option<&'v mut Item> {
+        match *v {
+            Item::ArrayOfTables(ref mut vec) => vec.values.get_mut(*self),
+            Item::Value(ref mut a) => a.as_array_mut().and_then(|a| a.values.get_mut(*self)),
+            _ => None,
+        }
+    }
+}
+
+impl Index for str {
+    fn index<'v>(&self, v: &'v Item) -> Option<&'v Item> {
+        match *v {
+            Item::Table(ref t) => t.get(self),
+            Item::Value(ref v) => v
+                .as_inline_table()
+                .and_then(|t| t.items.get(self))
+                .and_then(|kv| {
+                    if !kv.value.is_none() {
+                        Some(&kv.value)
+                    } else {
+                        None
+                    }
+                }),
+            _ => None,
+        }
+    }
+    fn index_mut<'v>(&self, v: &'v mut Item) -> Option<&'v mut Item> {
+        if let Item::None = *v {
+            let mut t = InlineTable::default();
+            t.items.insert(
+                InternalString::from(self),
+                TableKeyValue::new(Key::new(self), Item::None),
+            );
+            *v = value(Value::InlineTable(t));
+        }
+        match *v {
+            Item::Table(ref mut t) => Some(t.entry(self).or_insert(Item::None)),
+            Item::Value(ref mut v) => v.as_inline_table_mut().map(|t| {
+                &mut t
+                    .items
+                    .entry(InternalString::from(self))
+                    .or_insert_with(|| TableKeyValue::new(Key::new(self), Item::None))
+                    .value
+            }),
+            _ => None,
+        }
+    }
+}
+
+impl Index for String {
+    fn index<'v>(&self, v: &'v Item) -> Option<&'v Item> {
+        self[..].index(v)
+    }
+    fn index_mut<'v>(&self, v: &'v mut Item) -> Option<&'v mut Item> {
+        self[..].index_mut(v)
+    }
+}
+
+impl<'a, T: ?Sized> Index for &'a T
+where
+    T: Index,
+{
+    fn index<'v>(&self, v: &'v Item) -> Option<&'v Item> {
+        (**self).index(v)
+    }
+    fn index_mut<'v>(&self, v: &'v mut Item) -> Option<&'v mut Item> {
+        (**self).index_mut(v)
+    }
+}
+
+impl<I> ops::Index<I> for Item
+where
+    I: Index,
+{
+    type Output = Item;
+
+    fn index(&self, index: I) -> &Item {
+        index.index(self).expect("index not found")
+    }
+}
+
+impl<I> ops::IndexMut<I> for Item
+where
+    I: Index,
+{
+    fn index_mut(&mut self, index: I) -> &mut Item {
+        index.index_mut(self).expect("index not found")
+    }
+}
+
+impl<'s> ops::Index<&'s str> for Table {
+    type Output = Item;
+
+    fn index(&self, key: &'s str) -> &Item {
+        self.get(key).expect("index not found")
+    }
+}
+
+impl<'s> ops::IndexMut<&'s str> for Table {
+    fn index_mut(&mut self, key: &'s str) -> &mut Item {
+        self.entry(key).or_insert(Item::None)
+    }
+}
+
+impl<'s> ops::Index<&'s str> for InlineTable {
+    type Output = Value;
+
+    fn index(&self, key: &'s str) -> &Value {
+        self.get(key).expect("index not found")
+    }
+}
+
+impl<'s> ops::IndexMut<&'s str> for InlineTable {
+    fn index_mut(&mut self, key: &'s str) -> &mut Value {
+        self.get_mut(key).expect("index not found")
+    }
+}
+
+impl<'s> ops::Index<&'s str> for Document {
+    type Output = Item;
+
+    fn index(&self, key: &'s str) -> &Item {
+        self.root.index(key)
+    }
+}
+
+impl<'s> ops::IndexMut<&'s str> for Document {
+    fn index_mut(&mut self, key: &'s str) -> &mut Item {
+        self.root.index_mut(key)
+    }
+}