Convert Value trait to a Object enum; add ObjectPtr type

This commit is contained in:
Eryn Wells 2017-04-21 19:28:39 -07:00
parent 1365ab71db
commit 89279e5a22

View file

@ -2,11 +2,34 @@
* Eryn Wells <eryn@erynwells.me>
*/
use std::fmt::Debug;
use std::fmt;
use std::any::Any;
pub trait Value: Debug + IsBool + IsChar + IsNumber + ValueEq {
fn as_value(&self) -> &Value;
type ObjectPtr = Option<Box<Object>>;
pub enum ObjectPtr {
/// Absence of a value. A null pointer.
Null,
/// A pointer to an object.
Ptr(Box<Object>),
}
#[derive(Debug)]
pub enum Object {
Bool(bool),
ByteVector(Vec<u8>),
Char(char),
Pair(ObjectPtr, ObjectPtr),
//Procedure/*( TODO: Something )*/,
//Record/*( TODO: Something )*/,
String(String),
Symbol(String),
Vector(Vec<ObjectPtr>),
}
pub trait IsNull {
fn is_null(&self) -> bool { false }
fn is_eof(&self) -> bool { false }
}
pub trait IsBool {
@ -20,7 +43,7 @@ pub trait IsChar {
}
pub trait IsNumber {
/// Should return `true` if this Value is a number type.
/// Should return `true` if this Value is any kind of number.
fn is_number(&self) -> bool { self.is_complex() || self.is_real() || self.is_rational() || self.is_integer() }
/// Should return `true` if this Value is a complex number type.
fn is_complex(&self) -> bool { self.is_real() }
@ -31,16 +54,3 @@ pub trait IsNumber {
/// Should return `true` if this Value is a integer number type.
fn is_integer(&self) -> bool { false }
}
/// A trait on value types that makes it easier to compare values of disparate types. The methods
/// provided by this trait are used by the PartialEq implementation on Values.
pub trait ValueEq {
fn eq(&self, other: &Value) -> bool;
fn as_any(&self) -> &Any;
}
impl<'lhs,'rhs> PartialEq<Value+'rhs> for Value+'lhs {
fn eq(&self, other: &(Value+'rhs)) -> bool {
ValueEq::eq(self, other)
}
}