use core::mem::size_of;
use core::num::Wrapping;
use core::{f32, f64};
#[cfg(has_i128)]
use core::{i128, u128};
use core::{i16, i32, i64, i8, isize};
use core::{u16, u32, u64, u8, usize};
use float::FloatCore;
pub trait ToPrimitive {
#[inline]
fn to_isize(&self) -> Option<isize> {
self.to_i64().as_ref().and_then(ToPrimitive::to_isize)
}
#[inline]
fn to_i8(&self) -> Option<i8> {
self.to_i64().as_ref().and_then(ToPrimitive::to_i8)
}
#[inline]
fn to_i16(&self) -> Option<i16> {
self.to_i64().as_ref().and_then(ToPrimitive::to_i16)
}
#[inline]
fn to_i32(&self) -> Option<i32> {
self.to_i64().as_ref().and_then(ToPrimitive::to_i32)
}
fn to_i64(&self) -> Option<i64>;
#[inline]
#[cfg(has_i128)]
fn to_i128(&self) -> Option<i128> {
self.to_i64().map(From::from)
}
#[inline]
fn to_usize(&self) -> Option<usize> {
self.to_u64().as_ref().and_then(ToPrimitive::to_usize)
}
#[inline]
fn to_u8(&self) -> Option<u8> {
self.to_u64().as_ref().and_then(ToPrimitive::to_u8)
}
#[inline]
fn to_u16(&self) -> Option<u16> {
self.to_u64().as_ref().and_then(ToPrimitive::to_u16)
}
#[inline]
fn to_u32(&self) -> Option<u32> {
self.to_u64().as_ref().and_then(ToPrimitive::to_u32)
}
fn to_u64(&self) -> Option<u64>;
#[inline]
#[cfg(has_i128)]
fn to_u128(&self) -> Option<u128> {
self.to_u64().map(From::from)
}
#[inline]
fn to_f32(&self) -> Option<f32> {
self.to_f64().as_ref().and_then(ToPrimitive::to_f32)
}
#[inline]
fn to_f64(&self) -> Option<f64> {
match self.to_i64() {
Some(i) => i.to_f64(),
None => self.to_u64().as_ref().and_then(ToPrimitive::to_f64),
}
}
}
macro_rules! impl_to_primitive_int_to_int {
($SrcT:ident : $( $(#[$cfg:meta])* fn $method:ident -> $DstT:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$DstT> {
let min = $DstT::MIN as $SrcT;
let max = $DstT::MAX as $SrcT;
if size_of::<$SrcT>() <= size_of::<$DstT>() || (min <= *self && *self <= max) {
Some(*self as $DstT)
} else {
None
}
}
)*}
}
macro_rules! impl_to_primitive_int_to_uint {
($SrcT:ident : $( $(#[$cfg:meta])* fn $method:ident -> $DstT:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$DstT> {
let max = $DstT::MAX as $SrcT;
if 0 <= *self && (size_of::<$SrcT>() <= size_of::<$DstT>() || *self <= max) {
Some(*self as $DstT)
} else {
None
}
}
)*}
}
macro_rules! impl_to_primitive_int {
($T:ident) => {
impl ToPrimitive for $T {
impl_to_primitive_int_to_int! { $T:
fn to_isize -> isize;
fn to_i8 -> i8;
fn to_i16 -> i16;
fn to_i32 -> i32;
fn to_i64 -> i64;
#[cfg(has_i128)]
fn to_i128 -> i128;
}
impl_to_primitive_int_to_uint! { $T:
fn to_usize -> usize;
fn to_u8 -> u8;
fn to_u16 -> u16;
fn to_u32 -> u32;
fn to_u64 -> u64;
#[cfg(has_i128)]
fn to_u128 -> u128;
}
#[inline]
fn to_f32(&self) -> Option<f32> {
Some(*self as f32)
}
#[inline]
fn to_f64(&self) -> Option<f64> {
Some(*self as f64)
}
}
};
}
impl_to_primitive_int!(isize);
impl_to_primitive_int!(i8);
impl_to_primitive_int!(i16);
impl_to_primitive_int!(i32);
impl_to_primitive_int!(i64);
#[cfg(has_i128)]
impl_to_primitive_int!(i128);
macro_rules! impl_to_primitive_uint_to_int {
($SrcT:ident : $( $(#[$cfg:meta])* fn $method:ident -> $DstT:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$DstT> {
let max = $DstT::MAX as $SrcT;
if size_of::<$SrcT>() < size_of::<$DstT>() || *self <= max {
Some(*self as $DstT)
} else {
None
}
}
)*}
}
macro_rules! impl_to_primitive_uint_to_uint {
($SrcT:ident : $( $(#[$cfg:meta])* fn $method:ident -> $DstT:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$DstT> {
let max = $DstT::MAX as $SrcT;
if size_of::<$SrcT>() <= size_of::<$DstT>() || *self <= max {
Some(*self as $DstT)
} else {
None
}
}
)*}
}
macro_rules! impl_to_primitive_uint {
($T:ident) => {
impl ToPrimitive for $T {
impl_to_primitive_uint_to_int! { $T:
fn to_isize -> isize;
fn to_i8 -> i8;
fn to_i16 -> i16;
fn to_i32 -> i32;
fn to_i64 -> i64;
#[cfg(has_i128)]
fn to_i128 -> i128;
}
impl_to_primitive_uint_to_uint! { $T:
fn to_usize -> usize;
fn to_u8 -> u8;
fn to_u16 -> u16;
fn to_u32 -> u32;
fn to_u64 -> u64;
#[cfg(has_i128)]
fn to_u128 -> u128;
}
#[inline]
fn to_f32(&self) -> Option<f32> {
Some(*self as f32)
}
#[inline]
fn to_f64(&self) -> Option<f64> {
Some(*self as f64)
}
}
};
}
impl_to_primitive_uint!(usize);
impl_to_primitive_uint!(u8);
impl_to_primitive_uint!(u16);
impl_to_primitive_uint!(u32);
impl_to_primitive_uint!(u64);
#[cfg(has_i128)]
impl_to_primitive_uint!(u128);
macro_rules! impl_to_primitive_float_to_float {
($SrcT:ident : $( fn $method:ident -> $DstT:ident ; )*) => {$(
#[inline]
fn $method(&self) -> Option<$DstT> {
if size_of::<$SrcT>() > size_of::<$DstT>() && FloatCore::is_finite(*self) {
let n = *self as f64;
if n < $DstT::MIN as f64 || n > $DstT::MAX as f64 {
return None;
}
}
Some(*self as $DstT)
}
)*}
}
macro_rules! impl_to_primitive_float_to_signed_int {
($f:ident : $( $(#[$cfg:meta])* fn $method:ident -> $i:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$i> {
if size_of::<$f>() > size_of::<$i>() {
const MIN_M1: $f = $i::MIN as $f - 1.0;
const MAX_P1: $f = $i::MAX as $f + 1.0;
if *self > MIN_M1 && *self < MAX_P1 {
return Some(*self as $i);
}
} else {
const MIN: $f = $i::MIN as $f;
const MAX_P1: $f = $i::MAX as $f;
if *self >= MIN && *self < MAX_P1 {
return Some(*self as $i);
}
}
None
}
)*}
}
macro_rules! impl_to_primitive_float_to_unsigned_int {
($f:ident : $( $(#[$cfg:meta])* fn $method:ident -> $u:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$u> {
if size_of::<$f>() > size_of::<$u>() {
const MAX_P1: $f = $u::MAX as $f + 1.0;
if *self > -1.0 && *self < MAX_P1 {
return Some(*self as $u);
}
} else {
const MAX_P1: $f = $u::MAX as $f;
if *self > -1.0 && *self < MAX_P1 {
return Some(*self as $u);
}
}
None
}
)*}
}
macro_rules! impl_to_primitive_float {
($T:ident) => {
impl ToPrimitive for $T {
impl_to_primitive_float_to_signed_int! { $T:
fn to_isize -> isize;
fn to_i8 -> i8;
fn to_i16 -> i16;
fn to_i32 -> i32;
fn to_i64 -> i64;
#[cfg(has_i128)]
fn to_i128 -> i128;
}
impl_to_primitive_float_to_unsigned_int! { $T:
fn to_usize -> usize;
fn to_u8 -> u8;
fn to_u16 -> u16;
fn to_u32 -> u32;
fn to_u64 -> u64;
#[cfg(has_i128)]
fn to_u128 -> u128;
}
impl_to_primitive_float_to_float! { $T:
fn to_f32 -> f32;
fn to_f64 -> f64;
}
}
};
}
impl_to_primitive_float!(f32);
impl_to_primitive_float!(f64);
pub trait FromPrimitive: Sized {
#[inline]
fn from_isize(n: isize) -> Option<Self> {
n.to_i64().and_then(FromPrimitive::from_i64)
}
#[inline]
fn from_i8(n: i8) -> Option<Self> {
FromPrimitive::from_i64(From::from(n))
}
#[inline]
fn from_i16(n: i16) -> Option<Self> {
FromPrimitive::from_i64(From::from(n))
}
#[inline]
fn from_i32(n: i32) -> Option<Self> {
FromPrimitive::from_i64(From::from(n))
}
fn from_i64(n: i64) -> Option<Self>;
#[inline]
#[cfg(has_i128)]
fn from_i128(n: i128) -> Option<Self> {
n.to_i64().and_then(FromPrimitive::from_i64)
}
#[inline]
fn from_usize(n: usize) -> Option<Self> {
n.to_u64().and_then(FromPrimitive::from_u64)
}
#[inline]
fn from_u8(n: u8) -> Option<Self> {
FromPrimitive::from_u64(From::from(n))
}
#[inline]
fn from_u16(n: u16) -> Option<Self> {
FromPrimitive::from_u64(From::from(n))
}
#[inline]
fn from_u32(n: u32) -> Option<Self> {
FromPrimitive::from_u64(From::from(n))
}
fn from_u64(n: u64) -> Option<Self>;
#[inline]
#[cfg(has_i128)]
fn from_u128(n: u128) -> Option<Self> {
n.to_u64().and_then(FromPrimitive::from_u64)
}
#[inline]
fn from_f32(n: f32) -> Option<Self> {
FromPrimitive::from_f64(From::from(n))
}
#[inline]
fn from_f64(n: f64) -> Option<Self> {
match n.to_i64() {
Some(i) => FromPrimitive::from_i64(i),
None => n.to_u64().and_then(FromPrimitive::from_u64),
}
}
}
macro_rules! impl_from_primitive {
($T:ty, $to_ty:ident) => {
#[allow(deprecated)]
impl FromPrimitive for $T {
#[inline]
fn from_isize(n: isize) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_i8(n: i8) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_i16(n: i16) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_i32(n: i32) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_i64(n: i64) -> Option<$T> {
n.$to_ty()
}
#[cfg(has_i128)]
#[inline]
fn from_i128(n: i128) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_usize(n: usize) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_u8(n: u8) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_u16(n: u16) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_u32(n: u32) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_u64(n: u64) -> Option<$T> {
n.$to_ty()
}
#[cfg(has_i128)]
#[inline]
fn from_u128(n: u128) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_f32(n: f32) -> Option<$T> {
n.$to_ty()
}
#[inline]
fn from_f64(n: f64) -> Option<$T> {
n.$to_ty()
}
}
};
}
impl_from_primitive!(isize, to_isize);
impl_from_primitive!(i8, to_i8);
impl_from_primitive!(i16, to_i16);
impl_from_primitive!(i32, to_i32);
impl_from_primitive!(i64, to_i64);
#[cfg(has_i128)]
impl_from_primitive!(i128, to_i128);
impl_from_primitive!(usize, to_usize);
impl_from_primitive!(u8, to_u8);
impl_from_primitive!(u16, to_u16);
impl_from_primitive!(u32, to_u32);
impl_from_primitive!(u64, to_u64);
#[cfg(has_i128)]
impl_from_primitive!(u128, to_u128);
impl_from_primitive!(f32, to_f32);
impl_from_primitive!(f64, to_f64);
macro_rules! impl_to_primitive_wrapping {
($( $(#[$cfg:meta])* fn $method:ident -> $i:ident ; )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(&self) -> Option<$i> {
(self.0).$method()
}
)*}
}
impl<T: ToPrimitive> ToPrimitive for Wrapping<T> {
impl_to_primitive_wrapping! {
fn to_isize -> isize;
fn to_i8 -> i8;
fn to_i16 -> i16;
fn to_i32 -> i32;
fn to_i64 -> i64;
#[cfg(has_i128)]
fn to_i128 -> i128;
fn to_usize -> usize;
fn to_u8 -> u8;
fn to_u16 -> u16;
fn to_u32 -> u32;
fn to_u64 -> u64;
#[cfg(has_i128)]
fn to_u128 -> u128;
fn to_f32 -> f32;
fn to_f64 -> f64;
}
}
macro_rules! impl_from_primitive_wrapping {
($( $(#[$cfg:meta])* fn $method:ident ( $i:ident ); )*) => {$(
#[inline]
$(#[$cfg])*
fn $method(n: $i) -> Option<Self> {
T::$method(n).map(Wrapping)
}
)*}
}
impl<T: FromPrimitive> FromPrimitive for Wrapping<T> {
impl_from_primitive_wrapping! {
fn from_isize(isize);
fn from_i8(i8);
fn from_i16(i16);
fn from_i32(i32);
fn from_i64(i64);
#[cfg(has_i128)]
fn from_i128(i128);
fn from_usize(usize);
fn from_u8(u8);
fn from_u16(u16);
fn from_u32(u32);
fn from_u64(u64);
#[cfg(has_i128)]
fn from_u128(u128);
fn from_f32(f32);
fn from_f64(f64);
}
}
#[inline]
pub fn cast<T: NumCast, U: NumCast>(n: T) -> Option<U> {
NumCast::from(n)
}
pub trait NumCast: Sized + ToPrimitive {
fn from<T: ToPrimitive>(n: T) -> Option<Self>;
}
macro_rules! impl_num_cast {
($T:ty, $conv:ident) => {
impl NumCast for $T {
#[inline]
#[allow(deprecated)]
fn from<N: ToPrimitive>(n: N) -> Option<$T> {
n.$conv()
}
}
};
}
impl_num_cast!(u8, to_u8);
impl_num_cast!(u16, to_u16);
impl_num_cast!(u32, to_u32);
impl_num_cast!(u64, to_u64);
#[cfg(has_i128)]
impl_num_cast!(u128, to_u128);
impl_num_cast!(usize, to_usize);
impl_num_cast!(i8, to_i8);
impl_num_cast!(i16, to_i16);
impl_num_cast!(i32, to_i32);
impl_num_cast!(i64, to_i64);
#[cfg(has_i128)]
impl_num_cast!(i128, to_i128);
impl_num_cast!(isize, to_isize);
impl_num_cast!(f32, to_f32);
impl_num_cast!(f64, to_f64);
impl<T: NumCast> NumCast for Wrapping<T> {
fn from<U: ToPrimitive>(n: U) -> Option<Self> {
T::from(n).map(Wrapping)
}
}
pub trait AsPrimitive<T>: 'static + Copy
where
T: 'static + Copy,
{
fn as_(self) -> T;
}
macro_rules! impl_as_primitive {
(@ $T: ty => $(#[$cfg:meta])* impl $U: ty ) => {
$(#[$cfg])*
impl AsPrimitive<$U> for $T {
#[inline] fn as_(self) -> $U { self as $U }
}
};
(@ $T: ty => { $( $U: ty ),* } ) => {$(
impl_as_primitive!(@ $T => impl $U);
)*};
($T: ty => { $( $U: ty ),* } ) => {
impl_as_primitive!(@ $T => { $( $U ),* });
impl_as_primitive!(@ $T => { u8, u16, u32, u64, usize });
impl_as_primitive!(@ $T => #[cfg(has_i128)] impl u128);
impl_as_primitive!(@ $T => { i8, i16, i32, i64, isize });
impl_as_primitive!(@ $T => #[cfg(has_i128)] impl i128);
};
}
impl_as_primitive!(u8 => { char, f32, f64 });
impl_as_primitive!(i8 => { f32, f64 });
impl_as_primitive!(u16 => { f32, f64 });
impl_as_primitive!(i16 => { f32, f64 });
impl_as_primitive!(u32 => { f32, f64 });
impl_as_primitive!(i32 => { f32, f64 });
impl_as_primitive!(u64 => { f32, f64 });
impl_as_primitive!(i64 => { f32, f64 });
#[cfg(has_i128)]
impl_as_primitive!(u128 => { f32, f64 });
#[cfg(has_i128)]
impl_as_primitive!(i128 => { f32, f64 });
impl_as_primitive!(usize => { f32, f64 });
impl_as_primitive!(isize => { f32, f64 });
impl_as_primitive!(f32 => { f32, f64 });
impl_as_primitive!(f64 => { f32, f64 });
impl_as_primitive!(char => { char });
impl_as_primitive!(bool => {});