rhai/types/
float.rs

1#![cfg(not(feature = "no_float"))]
2
3#[cfg(feature = "no_std")]
4use std::prelude::v1::*;
5use std::{
6    fmt,
7    hash::{Hash, Hasher},
8    ops::{Deref, DerefMut},
9    str::FromStr,
10};
11
12use num_traits::float::FloatCore as Float;
13
14/// _(internals)_ A type that wraps a floating-point number and implements [`Hash`].
15/// Exported under the `internals` feature only.
16///
17/// Not available under `no_float`.
18#[derive(Clone, Copy, Eq, PartialEq, PartialOrd)]
19#[must_use]
20pub struct FloatWrapper<F>(F);
21
22impl Hash for FloatWrapper<crate::FLOAT> {
23    #[inline]
24    fn hash<H: Hasher>(&self, state: &mut H) {
25        self.0.to_ne_bytes().hash(state);
26    }
27}
28
29impl<F: Float> AsRef<F> for FloatWrapper<F> {
30    #[inline(always)]
31    fn as_ref(&self) -> &F {
32        &self.0
33    }
34}
35
36impl<F: Float> AsMut<F> for FloatWrapper<F> {
37    #[inline(always)]
38    fn as_mut(&mut self) -> &mut F {
39        &mut self.0
40    }
41}
42
43impl<F: Float> Deref for FloatWrapper<F> {
44    type Target = F;
45
46    #[inline(always)]
47    fn deref(&self) -> &Self::Target {
48        &self.0
49    }
50}
51
52impl<F: Float> DerefMut for FloatWrapper<F> {
53    #[inline(always)]
54    fn deref_mut(&mut self) -> &mut Self::Target {
55        &mut self.0
56    }
57}
58
59impl<F: Float + fmt::Debug> fmt::Debug for FloatWrapper<F> {
60    #[cold]
61    #[inline(never)]
62    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
63        fmt::Debug::fmt(&self.0, f)
64    }
65}
66
67impl<F: Float + fmt::Display + fmt::LowerExp + From<f32>> fmt::Display for FloatWrapper<F> {
68    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
69        let abs = self.0.abs();
70        if abs.is_zero() {
71            f.write_str("0.0")
72        } else if abs > Self::MAX_NATURAL_FLOAT_FOR_DISPLAY.into()
73            || abs < Self::MIN_NATURAL_FLOAT_FOR_DISPLAY.into()
74        {
75            write!(f, "{:e}", self.0)
76        } else {
77            fmt::Display::fmt(&self.0, f)?;
78            if abs.fract().is_zero() {
79                f.write_str(".0")?;
80            }
81            Ok(())
82        }
83    }
84}
85
86impl<F: Float> From<F> for FloatWrapper<F> {
87    #[inline(always)]
88    fn from(value: F) -> Self {
89        Self::new(value)
90    }
91}
92
93impl<F: Float + FromStr> FromStr for FloatWrapper<F> {
94    type Err = <F as FromStr>::Err;
95
96    #[inline]
97    fn from_str(s: &str) -> Result<Self, Self::Err> {
98        F::from_str(s).map(Into::into)
99    }
100}
101
102impl<F: Float> FloatWrapper<F> {
103    /// Maximum floating-point number for natural display before switching to scientific notation.
104    pub const MAX_NATURAL_FLOAT_FOR_DISPLAY: f32 = 10_000_000_000_000.0;
105
106    /// Minimum floating-point number for natural display before switching to scientific notation.
107    pub const MIN_NATURAL_FLOAT_FOR_DISPLAY: f32 = 0.000_000_000_000_1;
108
109    /// Create a new [`FloatWrapper`].
110    #[inline(always)]
111    pub const fn new(value: F) -> Self {
112        Self(value)
113    }
114}
rhai/types/float.rs

rhai/types/
float.rs
