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#![no_std]
pub trait AsPrim : 'static + Copy {
fn as_usize(self) -> usize;
fn as_isize(self) -> isize;
fn as_u64(self) -> u64;
fn as_i64(self) -> i64;
fn as_u32(self) -> u32;
fn as_i32(self) -> i32;
fn as_u16(self) -> u16;
fn as_i16(self) -> i16;
fn as_u8(self) -> u8;
fn as_i8(self) -> i8;
fn as_f32(self) -> f32;
fn as_f64(self) -> f64;
fn cast_from<T: AsPrim>(T) -> Self;
#[inline(always)]
fn as_<T: AsPrim>(self) -> T {
T::cast_from(self)
}
}
macro_rules! as_prim_impl {
($($method:ident $from:ty)*) => {
$(
impl AsPrim for $from {
#[inline(always)]
fn as_usize(self) -> usize { self as usize }
#[inline(always)]
fn as_isize(self) -> isize { self as isize }
#[inline(always)]
fn as_u64(self) -> u64 { self as u64 }
#[inline(always)]
fn as_i64(self) -> i64 { self as i64 }
#[inline(always)]
fn as_u32(self) -> u32 { self as u32 }
#[inline(always)]
fn as_i32(self) -> i32 { self as i32 }
#[inline(always)]
fn as_u16(self) -> u16 { self as u16 }
#[inline(always)]
fn as_i16(self) -> i16 { self as i16 }
#[inline(always)]
fn as_u8(self) -> u8 { self as u8 }
#[inline(always)]
fn as_i8(self) -> i8 { self as i8 }
#[inline(always)]
fn as_f32(self) -> f32 { self as f32 }
#[inline(always)]
fn as_f64(self) -> f64 { self as f64 }
#[inline(always)]
fn cast_from<T: AsPrim>(x: T) -> Self {
x.$method()
}
}
)*
}
}
as_prim_impl!{as_u8 u8 as_i8 i8 as_u16 u16 as_i16 i16 as_u32 u32 as_i32 i32
as_u64 u64 as_i64 i64 as_usize usize as_isize isize as_f32 f32 as_f64 f64}
#[cfg(test)]
mod tests {
use AsPrim;
#[test]
fn it_works() {
assert_eq!(1.as_::<f32>(), 1.0);
}
}