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#![cfg_attr(feature="unstable", feature(unboxed_closures, core))]
extern crate unreachable;
mod range;
mod fix;
pub mod string;
pub mod vec;
pub use fix::Fix;
pub use range::IndexRange;
use unreachable::unreachable;
use std::{slice, mem};
#[inline]
pub fn ref_eq<T>(a: &T, b: &T) -> bool {
ptr_eq(a, b)
}
#[inline]
pub fn ptr_eq<T>(a: *const T, b: *const T) -> bool {
a == b
}
#[inline]
pub unsafe fn raw_byte_repr<T: ?Sized>(ptr: &T) -> &[u8] {
slice::from_raw_parts(
ptr as *const _ as *const u8,
mem::size_of_val(ptr),
)
}
#[inline]
pub unsafe fn get_unchecked<T>(data: &[T], index: usize) -> &T {
debug_assert!(index < data.len());
data.get_unchecked(index)
}
#[inline]
pub unsafe fn get_unchecked_mut<T>(data: &mut [T], index: usize) -> &mut T {
debug_assert!(index < data.len());
data.get_unchecked_mut(index)
}
#[inline(always)]
pub unsafe fn debug_assert_unreachable() -> ! {
debug_assert!(false, "Entered unreachable section, this is a bug!");
unreachable()
}
#[inline]
pub unsafe fn slice_unchecked<T>(data: &[T], from: usize, to: usize) -> &[T] {
debug_assert!((&data[from..to], true).1);
std::slice::from_raw_parts(data.as_ptr().offset(from as isize), to - from)
}
#[test]
fn test_repr() {
unsafe {
assert_eq!(raw_byte_repr(&17u8), &[17]);
assert_eq!(raw_byte_repr("abc"), "abc".as_bytes());
}
}
#[test]
#[should_panic]
fn test_get_unchecked_1() {
if cfg!(not(debug_assertions)) {
panic!();
}
unsafe {
get_unchecked(&[1, 2, 3], 3);
}
}
#[test]
#[should_panic]
fn test_slice_unchecked_1() {
if cfg!(not(debug_assertions)) {
panic!();
}
unsafe {
slice_unchecked(&[1, 2, 3], 0, 4);
}
}
#[test]
#[should_panic]
fn test_slice_unchecked_2() {
if cfg!(not(debug_assertions)) {
panic!();
}
unsafe {
slice_unchecked(&[1, 2, 3], 4, 4);
}
}
#[test]
fn test_slice_unchecked_3() {
let data = [1, 2, 3, 4];
let sl = &data[0..0];
if cfg!(debug_assertions) {
} else {
unsafe {
assert_eq!(slice_unchecked(sl, 0, 4), &[1, 2, 3, 4]);
}
}
}