use std::cell::RefCell;
use std::rc::Rc;
use std::ops::{Add, Sub};
use super::{IncrBy, DecrBy};
use super::action::{TypedAction, Action, ParseResult};
use super::action::ParseResult::Parsed;
use super::action::IFlagAction;
use super::action::Action::Flag;
pub struct IncrByAction<'a, T: 'a> {
delta: T,
cell: Rc<RefCell<&'a mut T>>,
}
pub struct DecrByAction<'a, T: 'a> {
delta: T,
cell: Rc<RefCell<&'a mut T>>,
}
impl<T: 'static + Add<Output = T> + Clone> TypedAction<T> for IncrBy<T> {
fn bind<'x>(&self, cell: Rc<RefCell<&'x mut T>>) -> Action<'x> {
let IncrBy(ref delta) = *self;
return Flag(Box::new(IncrByAction { cell: cell, delta: delta.clone() }));
}
}
impl<T: 'static + Sub<Output = T> + Clone> TypedAction<T> for DecrBy<T> {
fn bind<'x>(&self, cell: Rc<RefCell<&'x mut T>>) -> Action<'x> {
let DecrBy(ref delta) = *self;
return Flag(Box::new(DecrByAction { cell: cell, delta: delta.clone() }));
}
}
impl<'a, T: Add<Output = T> + Clone> IFlagAction for IncrByAction<'a, T> {
fn parse_flag(&self) -> ParseResult {
let oldval = {
let targ = self.cell.borrow();
targ.clone()
};
let mut targ = self.cell.borrow_mut();
**targ = oldval + self.delta.clone();
return Parsed;
}
}
impl<'a, T: Sub<Output = T> + Clone> IFlagAction for DecrByAction<'a, T> {
fn parse_flag(&self) -> ParseResult {
let oldval = {
let targ = self.cell.borrow();
targ.clone()
};
let mut targ = self.cell.borrow_mut();
**targ = oldval - self.delta.clone();
return Parsed;
}
}