ladata/mem/size/
mod.rs

1// ladata::mem::size
2//
3//! Traits related to memory size.
4//
5
6use core::mem::{size_of, size_of_val};
7
8mod bit_size;
9pub use bit_size::*;
10
11impl<T> DataSize for T {}
12
13/// Convenience trait for Size related information.
14///
15/// It is automatically implemented for every sized type.
16pub trait DataSize: Sized {
17    /// The size of this type in bytes, rounded up if it's not a multiple of 8.
18    const BYTES: usize = size_of::<Self>();
19
20    /// The pointer size in bits for the current platform.
21    const UBITS: usize = Self::UBYTES * 8;
22
23    /// The pointer size in bytes for the current platform.
24    const UBYTES: usize = size_of::<usize>();
25
26    /// Returns the size ratio between [`UBYTES`][Self#constant.UBYTES] and
27    /// [`BYTES`][Self#constant.BYTES].
28    ///
29    /// For example: the ratio will be (1, 1) if both sizes are the same,
30    /// (2, 1) if a pointer is double the byte size, and (1, 2) if a pointer is
31    /// half the byte size.
32    ///
33    /// # Examples
34    /// ```
35    /// use ladata::all::DataSize;
36    ///
37    /// assert_eq![1_usize.pointer_ratio(), (1, 1)];
38    /// assert_eq!["slice".pointer_ratio(), (1, 2)];
39    /// assert_eq![String::new().pointer_ratio(), (1, 3)];
40    ///
41    /// #[cfg(target_pointer_width = "64")]
42    /// assert_eq!['a'.pointer_ratio(), (2,1)]
43    /// ```
44    fn pointer_ratio(&self) -> (usize, usize) {
45        #[inline]
46        fn gcd(m: usize, n: usize) -> usize {
47            if n == 0 {
48                m
49            } else {
50                gcd(n, m % n)
51            }
52        }
53        let g = gcd(Self::UBYTES, Self::BYTES);
54        (Self::UBYTES / g, Self::BYTES / g)
55    }
56
57    /// Returns the size in bytes of this type, in the stack.
58    ///
59    /// Ignores any allocated resources in the heap.
60    fn stack_byte_size(&self) -> usize {
61        size_of_val(self)
62    }
63
64    // /// Returns the size in bytes of this type, in the heap.
65    // fn heap_byte_size(&self) -> usize {
66    //     todo![] // TODO
67    // }
68}
ladata/mem/size/mod.rs

ladata/mem/size/
mod.rs
