1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36

use num::arithmetic::traits::{OverflowingMul, OverflowingMulAssign};

macro_rules! impl_overflowing_mul {
    ($t:ident) => {
        impl OverflowingMul<$t> for $t {
            type Output = $t;

            /// This is a wrapper over the `overflowing_mul` functions in the standard library, for
            /// example [this one](u32::overflowing_mul).
            #[inline]
            fn overflowing_mul(self, other: $t) -> ($t, bool) {
                $t::overflowing_mul(self, other)
            }
        }

        impl OverflowingMulAssign<$t> for $t {
            /// Multiplies a number by another number, in place.
            ///
            /// Returns a boolean indicating whether an arithmetic overflow occurred. If an
            /// overflow occurred, then the wrapped value is assigned.
            ///
            /// # Worst-case complexity
            /// Constant time and additional memory.
            ///
            /// # Examples
            /// See [here](super::overflowing_mul#overflowing_mul_assign).
            #[inline]
            fn overflowing_mul_assign(&mut self, other: $t) -> bool {
                let overflow;
                (*self, overflow) = self.overflowing_mul(other);
                overflow
            }
        }
    };
}
apply_to_primitive_ints!(impl_overflowing_mul);