1 files changed, 138 insertions, 0 deletions
diff --git a/src/value.rs b/src/value.rs
new file mode 100644
index 0000000..b3b4f2f
--- /dev/null
+++ b/src/value.rs
@@ -0,0 +1,138 @@
+use std::str;
+use std::ops::{Deref, DerefMut};
+use std::iter::FromIterator;
+use std::collections::VecDeque;
+
+use error::*;
+use types::{Integer, LightUserData, Number};
+use string::String;
+use table::Table;
+use function::Function;
+use thread::Thread;
+use userdata::AnyUserData;
+use lua::Lua;
+
+/// A dynamically typed Lua value.
+#[derive(Debug, Clone)]
+pub enum Value<'lua> {
+    /// The Lua value `nil`.
+    Nil,
+    /// The Lua value `true` or `false`.
+    Boolean(bool),
+    /// A "light userdata" object, equivalent to a raw pointer.
+    LightUserData(LightUserData),
+    /// An integer number.
+    ///
+    /// Any Lua number convertible to a `Integer` will be represented as this variant.
+    Integer(Integer),
+    /// A floating point number.
+    Number(Number),
+    /// An interned string, managed by Lua.
+    ///
+    /// Unlike Rust strings, Lua strings may not be valid UTF-8.
+    String(String<'lua>),
+    /// Reference to a Lua table.
+    Table(Table<'lua>),
+    /// Reference to a Lua function (or closure).
+    Function(Function<'lua>),
+    /// Reference to a Lua thread (or coroutine).
+    Thread(Thread<'lua>),
+    /// Reference to a userdata object that holds a custom type which implements `UserData`.
+    /// Special builtin userdata types will be represented as other `Value` variants.
+    UserData(AnyUserData<'lua>),
+    /// `Error` is a special builtin userdata type.  When received from Lua it is implicitly cloned.
+    Error(Error),
+}
+pub use self::Value::Nil;
+
+impl<'lua> Value<'lua> {
+    pub(crate) fn type_name(&self) -> &'static str {
+        match *self {
+            Value::Nil => "nil",
+            Value::Boolean(_) => "boolean",
+            Value::LightUserData(_) => "light userdata",
+            Value::Integer(_) => "integer",
+            Value::Number(_) => "number",
+            Value::String(_) => "string",
+            Value::Table(_) => "table",
+            Value::Function(_) => "function",
+            Value::Thread(_) => "thread",
+            Value::UserData(_) | Value::Error(_) => "userdata",
+        }
+    }
+}
+
+/// Trait for types convertible to `Value`.
+pub trait ToLua<'lua> {
+    /// Performs the conversion.
+    fn to_lua(self, lua: &'lua Lua) -> Result<Value<'lua>>;
+}
+
+/// Trait for types convertible from `Value`.
+pub trait FromLua<'lua>: Sized {
+    /// Performs the conversion.
+    fn from_lua(lua_value: Value<'lua>, lua: &'lua Lua) -> Result<Self>;
+}
+
+/// Multiple Lua values used for both argument passing and also for multiple return values.
+#[derive(Debug, Clone)]
+pub struct MultiValue<'lua>(VecDeque<Value<'lua>>);
+
+impl<'lua> MultiValue<'lua> {
+    /// Creates an empty `MultiValue` containing no values.
+    pub fn new() -> MultiValue<'lua> {
+        MultiValue(VecDeque::new())
+    }
+}
+
+impl<'lua> FromIterator<Value<'lua>> for MultiValue<'lua> {
+    fn from_iter<I: IntoIterator<Item = Value<'lua>>>(iter: I) -> Self {
+        MultiValue(VecDeque::from_iter(iter))
+    }
+}
+
+impl<'lua> IntoIterator for MultiValue<'lua> {
+    type Item = Value<'lua>;
+    type IntoIter = <VecDeque<Value<'lua>> as IntoIterator>::IntoIter;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.into_iter()
+    }
+}
+
+impl<'lua> Deref for MultiValue<'lua> {
+    type Target = VecDeque<Value<'lua>>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<'lua> DerefMut for MultiValue<'lua> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
+/// Trait for types convertible to any number of Lua values.
+///
+/// This is a generalization of `ToLua`, allowing any number of resulting Lua values instead of just
+/// one. Any type that implements `ToLua` will automatically implement this trait.
+pub trait ToLuaMulti<'lua> {
+    /// Performs the conversion.
+    fn to_lua_multi(self, lua: &'lua Lua) -> Result<MultiValue<'lua>>;
+}
+
+/// Trait for types that can be created from an arbitrary number of Lua values.
+///
+/// This is a generalization of `FromLua`, allowing an arbitrary number of Lua values to participate
+/// in the conversion. Any type that implements `FromLua` will automatically implement this trait.
+pub trait FromLuaMulti<'lua>: Sized {
+    /// Performs the conversion.
+    ///
+    /// In case `values` contains more values than needed to perform the conversion, the excess
+    /// values should be ignored. This reflects the semantics of Lua when calling a function or
+    /// assigning values. Similarly, if not enough values are given, conversions should assume that
+    /// any missing values are nil.
+    fn from_lua_multi(values: MultiValue<'lua>, lua: &'lua Lua) -> Result<Self>;
+}