ndarray/
math_cell.rs

1
2use std::cell::Cell;
3use std::cmp::Ordering;
4use std::fmt;
5
6use std::ops::{Deref, DerefMut};
7
8/// A transparent wrapper of [`Cell<T>`](std::cell::Cell) which is identical in every way, except
9/// it will implement arithmetic operators as well.
10///
11/// The purpose of `MathCell` is to be used from [.cell_view()](crate::ArrayBase::cell_view).
12/// The `MathCell` derefs to `Cell`, so all the cell's methods are available.
13#[repr(transparent)]
14#[derive(Default)]
15pub struct MathCell<T>(Cell<T>);
16
17impl<T> MathCell<T> {
18    /// Create a new cell with the given value
19    #[inline(always)]
20    pub const fn new(value: T) -> Self { MathCell(Cell::new(value)) }
21
22    /// Return the inner value
23    pub fn into_inner(self) -> T { Cell::into_inner(self.0) }
24
25    /// Swap value with another cell
26    pub fn swap(&self, other: &Self) {
27        Cell::swap(&self.0, &other.0)
28    }
29}
30
31impl<T> Deref for MathCell<T> {
32    type Target = Cell<T>;
33    #[inline(always)]
34    fn deref(&self) -> &Self::Target { &self.0 }
35}
36
37impl<T> DerefMut for MathCell<T> {
38    #[inline(always)]
39    fn deref_mut(&mut self) -> &mut Self::Target { &mut self.0 }
40}
41
42impl<T> Clone for MathCell<T>
43    where T: Copy
44{
45    fn clone(&self) -> Self {
46        MathCell::new(self.get())
47    }
48}
49
50impl<T> PartialEq for MathCell<T>
51    where T: Copy + PartialEq
52{
53    fn eq(&self, rhs: &Self) -> bool {
54        self.get() == rhs.get()
55    }
56}
57
58impl<T> Eq for MathCell<T>
59    where T: Copy + Eq
60{ }
61
62impl<T> PartialOrd for MathCell<T>
63    where T: Copy + PartialOrd
64{
65    fn partial_cmp(&self, rhs: &Self) -> Option<Ordering> {
66        self.get().partial_cmp(&rhs.get())
67    }
68
69    fn lt(&self, rhs: &Self) -> bool { self.get().lt(&rhs.get()) }
70    fn le(&self, rhs: &Self) -> bool { self.get().le(&rhs.get()) }
71    fn gt(&self, rhs: &Self) -> bool { self.get().gt(&rhs.get()) }
72    fn ge(&self, rhs: &Self) -> bool { self.get().ge(&rhs.get()) }
73}
74
75impl<T> Ord for MathCell<T>
76    where T: Copy + Ord
77{
78    fn cmp(&self, rhs: &Self) -> Ordering {
79        self.get().cmp(&rhs.get())
80    }
81}
82
83impl<T> fmt::Debug for MathCell<T>
84    where T: Copy + fmt::Debug
85{
86    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
87        self.get().fmt(f)
88    }
89}
90
91
92#[cfg(test)]
93mod tests {
94    use super::MathCell;
95
96    #[test]
97    fn test_basic() {
98        let c = &MathCell::new(0);
99        c.set(1);
100        assert_eq!(c.get(), 1);
101    }
102}
ndarray/math_cell.rs

ndarray/
math_cell.rs
