Trait alloc::slice::SliceIndex

pub unsafe trait SliceIndex<T>: Sealed where
    T: ?Sized, {
    type Output: ?Sized;
    fn get(self, slice: &T) -> Option<&Self::Output>;
    fn get_mut(self, slice: &mut T) -> Option<&mut Self::Output>;
    unsafe fn get_unchecked(self, slice: *const T) -> *const Self::Output;
    unsafe fn get_unchecked_mut(self, slice: *mut T) -> *mut Self::Output;
    fn index(self, slice: &T) -> &Self::Output;
    fn index_mut(self, slice: &mut T) -> &mut Self::Output;
}

帮助程序 trait 用于索引操作。

trait 的实现必须针对 promise，如果 get_(mut_)unchecked 的参数是安全引用，则结果也是如此。

Associated Types

type Output: ?Sized

方法返回的输出类型。

Required methods

fn get(self, slice: &T) -> Option<&Self::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

如果在边界内，则返回此位置输出的共享引用。

fn get_mut(self, slice: &mut T) -> Option<&mut Self::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

如果在边界内，则对此位置的输出返回一个可变引用。

unsafe fn get_unchecked(self, slice: *const T) -> *const Self::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

返回此位置输出的共享引用，而不执行任何边界检查。 即使未使用所得的引用，使用越界索引或悬空的 slice 指针调用此方法也是 [undefined 行为]。

unsafe fn get_unchecked_mut(self, slice: *mut T) -> *mut Self::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

返回此位置输出的变量引用，而不执行任何边界检查。 即使未使用所得的引用，使用越界索引或悬空的 slice 指针调用此方法也是 [undefined 行为]。

fn index(self, slice: &T) -> &Self::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

返回此位置输出的共享引用，如果越界则会触发 panic。

fn index_mut(self, slice: &mut T) -> &mut Self::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

返回此位置输出的变量引用，如果越界则会触发 panic。

Implementations on Foreign Types

impl<T> SliceIndex<[T]> for RangeFrom<usize>

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for RangeTo<usize>

使用语法 &self[.. end] 或 &mut self[.. end] 实现子字符串切片。

从字节范围 [0，end) 返回给定字符串的片段。 等效于 &self[0 .. end] 或 &mut self[0 .. end]。

此运算为 O(1)。

在 1.20.0 之前，Index 和 IndexMut 的直接实现仍支持这些索引操作。

Panics

如果 end 没有指向字符的起始字节偏移量 (由 is_char_boundary 定义)，或者 end > len，则为 Panics。

type Output = str

pub fn get(
    self,
    slice: &str
) -> Option<&<RangeTo<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <RangeTo<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <RangeTo<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <RangeTo<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &str) -> &<RangeTo<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <RangeTo<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for RangeTo<usize>

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for RangeFrom<usize>

使用语法 &self[begin ..] 或 &mut self[begin ..] 实现子字符串切片。

从字节范围 [begin，len) 返回给定字符串的片段。等同于 &self[begin .. len]或&mut self[begin .. len]`.

此运算为 O(1)。

在 1.20.0 之前，Index 和 IndexMut 的直接实现仍支持这些索引操作。

Panics

如果 begin 没有指向字符的起始字节偏移量 (由 is_char_boundary 定义)，或者 begin > len，则为 Panics。

type Output = str

pub fn get(
    self,
    slice: &str
) -> Option<&<RangeFrom<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <RangeFrom<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <RangeFrom<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <RangeFrom<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(
    self,
    slice: &str
) -> &<RangeFrom<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <RangeFrom<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for RangeToInclusive<usize>

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for Range<usize>

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for RangeToInclusive<usize>

使用语法 &self[..= end] 或 &mut self[..= end] 实现子字符串切片。

从字节范围 [0, end] 返回给定字符串的片段。 等效于 &self [0 .. end + 1]，除非 end 具有 usize 的最大值。

此运算为 O(1)。

Panics

如果 end 没有指向字符的结束字节偏移量 (end + 1 是 is_char_boundary 定义的起始字节偏移量，或者等于 len)，或者如果 end >= len，则为 Panics。

type Output = str

pub fn get(
    self,
    slice: &str
) -> Option<&<RangeToInclusive<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <RangeToInclusive<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <RangeToInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <RangeToInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(
    self,
    slice: &str
) -> &<RangeToInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <RangeToInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for Range<usize>

使用语法 &self[begin .. end] 或 &mut self[begin .. end] 实现子字符串切片。

从字节范围 [begin，end`) 返回给定字符串的片段。

此运算为 O(1)。

在 1.20.0 之前，Index 和 IndexMut 的直接实现仍支持这些索引操作。

Panics

如果 begin 或 end 未指向字符的起始字节偏移量 (由 is_char_boundary 定义)，begin > end 或 end > len，则为 Panics。

Examples

let s = "Löwe 老虎 Léopard";
assert_eq!(&s[0 .. 1], "L");

assert_eq!(&s[1 .. 9], "öwe 老");

// 这些将是 panic:
// 字节 2 位于 `ö` 内:
// &s[2 ..3];

// byte 8 lies within `老` &s[1 ..
// 8];

// 字节 100 在字符串 &s[3 之外。
// 100];

type Output = str

pub fn get(
    self,
    slice: &str
) -> Option<&<Range<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <Range<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <Range<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <Range<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &str) -> &<Range<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <Range<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for RangeFull

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for RangeFull

使用语法 &self[..] 或 &mut self[..] 实现子字符串切片。

返回整个字符串的片段，即返回 &self 或 &mut self。相当于 &self[0 .. len] 或 &mut self[0 .. len]. 与其他索引操作不同，此操作永远不能 panic。

此运算为 O(1)。

在 1.20.0 之前，Index 和 IndexMut 的直接实现仍支持这些索引操作。

等效于 &self[0 .. len] 或 &mut self[0 .. len]。

type Output = str

pub fn get(self, slice: &str) -> Option<&<RangeFull as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <RangeFull as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <RangeFull as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <RangeFull as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &str) -> &<RangeFull as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <RangeFull as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl SliceIndex<str> for RangeInclusive<usize>

使用语法 &self[begin ..= end] 或 &mut self[begin ..= end] 实现子字符串切片。

从字节范围 [begin, end] 返回给定字符串的片段。等效于 &self [begin .. end + 1] 或 &mut self[begin .. end + 1]，除非 end 具有 usize 的最大值。

此运算为 O(1)。

Panics

Panics，如果 begin 不指向字符的起始字节偏移 (由 is_char_boundary 定义)，如果 end 不指向字符的终止字节偏移 (end + 1 是起始字节偏移或等于 len)，如果 begin > end，如果是 end >= len。

type Output = str

pub fn get(
    self,
    slice: &str
) -> Option<&<RangeInclusive<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut str
) -> Option<&mut <RangeInclusive<usize> as SliceIndex<str>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const str
) -> *const <RangeInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut str
) -> *mut <RangeInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(
    self,
    slice: &str
) -> &<RangeInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut str
) -> &mut <RangeInclusive<usize> as SliceIndex<str>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for RangeInclusive<usize>

type Output = [T]

pub fn get(self, slice: &[T]) -> Option<&[T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut [T]>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &[T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut [T]

🔬 This is a nightly-only experimental API. (slice_index_methods)

Implementors

impl<T> SliceIndex<[T]> for (Bound<usize>, Bound<usize>)

type Output = [T]

pub fn get(
    self,
    slice: &[T]
) -> Option<&<(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(
    self,
    slice: &mut [T]
) -> Option<&mut <(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(
    self,
    slice: *const [T]
) -> *const <(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(
    self,
    slice: *mut [T]
) -> *mut <(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(
    self,
    slice: &[T]
) -> &<(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(
    self,
    slice: &mut [T]
) -> &mut <(Bound<usize>, Bound<usize>) as SliceIndex<[T]>>::Output

🔬 This is a nightly-only experimental API. (slice_index_methods)

impl<T> SliceIndex<[T]> for usize

type Output = T

pub fn get(self, slice: &[T]) -> Option<&T>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn get_mut(self, slice: &mut [T]) -> Option<&mut T>

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked(self, slice: *const [T]) -> *const T

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub unsafe fn get_unchecked_mut(self, slice: *mut [T]) -> *mut T

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index(self, slice: &[T]) -> &T

🔬 This is a nightly-only experimental API. (slice_index_methods)

pub fn index_mut(self, slice: &mut [T]) -> &mut T

🔬 This is a nightly-only experimental API. (slice_index_methods)