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// This file is part of caniuse-serde. It is subject to the license terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/caniuse-serde/master/COPYRIGHT. No part of predicator, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
// Copyright © 2017 The developers of caniuse-serde. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/caniuse-serde/master/COPYRIGHT.
/// A simple 'newtype' wrapper that represents a percentage
#[derive(Deserialize, Debug, Copy, Clone)]
pub struct UsagePercentage(f64);
impl<I: Into<f64>> From<I> for UsagePercentage
{
/// Converts from anything that can be represented as a f64 into a percentage.
/// Clamps values below zero (including negative zero and negative infinity) to positive zero.
/// Clamps NaN as positive zero.
/// Clamps values above one hundred (including positive infinity) to one hundred.
#[inline(always)]
fn from(value: I) -> Self
{
Self::clamp(value.into())
}
}
impl PartialEq for UsagePercentage
{
/// Partial Equality; total equality is also supported
#[inline(always)]
fn eq(&self, other: &Self) -> bool
{
self.0.eq(&other.0)
}
}
impl Eq for UsagePercentage
{
}
impl PartialOrd for UsagePercentage
{
/// Partial comparison
#[inline(always)]
fn partial_cmp(&self, other: &Self) -> Option<Ordering>
{
self.0.partial_cmp(&other.0)
}
}
impl Ord for UsagePercentage
{
/// Total comparison; always succeeds
#[inline(always)]
fn cmp(&self, other: &Self) -> Ordering
{
self.partial_cmp(other).unwrap_or(Ordering::Equal)
}
}
impl Hash for UsagePercentage
{
/// Hash
#[inline(always)]
fn hash<H: Hasher>(&self, state: &mut H)
{
self.to_bits().hash(state)
}
}
impl Display for UsagePercentage
{
/// Displays as a floating point value followed by a '%'
#[inline(always)]
fn fmt(&self, fmt: &mut Formatter) -> fmt::Result
{
write!(fmt, "{}%", self.0)
}
}
impl Default for UsagePercentage
{
/// Defaults to zero
#[inline(always)]
fn default() -> Self
{
Self::Zero
}
}
impl Add<UsagePercentage> for UsagePercentage
{
type Output = Self;
/// Add
#[inline(always)]
fn add(self, rhs: Self) -> Self::Output
{
Self::clamp(self.0 + rhs.0)
}
}
impl AddAssign<UsagePercentage> for UsagePercentage
{
/// Add in place
#[inline(always)]
fn add_assign(&mut self, rhs: Self)
{
*self = self.add(rhs)
}
}
impl Sub<UsagePercentage> for UsagePercentage
{
type Output = Self;
/// Subtract
#[inline(always)]
fn sub(self, rhs: Self) -> Self::Output
{
Self::clamp(self.0 - rhs.0)
}
}
impl SubAssign<UsagePercentage> for UsagePercentage
{
/// Subtract in place
#[inline(always)]
fn sub_assign(&mut self, rhs: Self)
{
*self = self.sub(rhs)
}
}
impl Deref for UsagePercentage
{
type Target = f64;
/// Dereferences to f64
#[inline(always)]
fn deref(&self) -> &Self::Target
{
&self.0
}
}
impl UsagePercentage
{
/// Represents 0%
pub const Zero: Self = UsagePercentage(0.0);
/// Represents 1%
pub const One: Self = UsagePercentage(1.0);
/// Represents 0.1%
pub const OnePerMille: Self = UsagePercentage(0.1);
/// Represents 0.01%
pub const OneBasisPoint: Self = UsagePercentage(0.01);
/// Represents the minimum, 0%; interchangeable with UsagePercentage::Zero
pub const Minimum: Self = UsagePercentage::Zero;
/// Represents 100%
pub const OneHundred: Self = UsagePercentage(100.0);
/// Represents the maximum, 100%; interchangeable with UsagePercentage::OneHundred
pub const Maximum: Self = UsagePercentage::OneHundred;
/// Converts from anything that can be represented as a f64 into a percentage.
/// Clamps values below zero (including negative zero and negative infinity) to positive zero.
/// Clamps NaN as positive zero.
/// Clamps values above one hundred (including positive infinity) to one hundred.
#[inline(always)]
pub fn new(value: f64) -> Self
{
Self::clamp(value)
}
/// Converts to a scalar, ie a percentage divided by 100
#[inline(always)]
pub fn to_scalar(self) -> f64
{
self.0 / 100.0
}
#[inline(always)]
fn clamp(value: f64) -> Self
{
if value.is_sign_negative() || value.is_nan()
{
UsagePercentage(0.0)
}
else if value.is_sign_positive() && (value > 100.0 || value.is_infinite())
{
UsagePercentage(100.0)
}
else
{
UsagePercentage(value)
}
}
}