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 37 38 39 40 41 42
// Copyright 2013 The Servo Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution. // // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your // option. This file may not be copied, modified, or distributed // except according to those terms. /// Trait for testing approximate equality pub trait ApproxEq<Eps> { /// Default epsilon value fn approx_epsilon() -> Eps; /// Returns `true` is this object is approximately equal to the other one, using /// a provided epsilon value. fn approx_eq_eps(&self, other: &Self, approx_epsilon: &Eps) -> bool; /// Returns `true` is this object is approximately equal to the other one, using /// the `approx_epsilon()` epsilon value. fn approx_eq(&self, other: &Self) -> bool { self.approx_eq_eps(other, &Self::approx_epsilon()) } } macro_rules! approx_eq { ($ty:ty, $eps:expr) => { impl ApproxEq<$ty> for $ty { #[inline] fn approx_epsilon() -> $ty { $eps } #[inline] fn approx_eq_eps(&self, other: &$ty, approx_epsilon: &$ty) -> bool { num_traits::Float::abs(*self - *other) < *approx_epsilon } } }; } approx_eq!(f32, 1.0e-6); approx_eq!(f64, 1.0e-6);