标准库是否提供了一种使用另一个与待分割的同类型切片作为分隔符来分割切片的方法?标准库文档列出了基于单个元素分隔符的方法,而不是基于切片的方法。
例如:一个由5个u64整数组成的切片[1u64, 4u64, 0u64, 0u64, 8u64]使用[0u64, 0u64]作为分隔符进行分割,将会得到两个切片[1u64, 4u64]和[8u64]。
[T]
的方法,但您可以自己实现。fn main() {
let a = [1, 4, 7, 0, 0, 8, 10, 0, 0];
let b = [0, 0];
let mut iter = split_subsequence(&a, &b);
assert_eq!(&[1, 4, 7], iter.next().unwrap());
assert_eq!(&[8, 10], iter.next().unwrap());
assert!(iter.next().unwrap().is_empty());
assert_eq!(None, iter.next());
}
pub struct SplitSubsequence<'a, 'b, T: 'a + 'b> {
slice: &'a [T],
needle: &'b [T],
ended: bool,
}
impl<'a, 'b, T: 'a + 'b + PartialEq> Iterator for SplitSubsequence<'a, 'b, T> {
type Item = &'a [T];
fn next(&mut self) -> Option<Self::Item> {
if self.ended {
None
} else if self.slice.is_empty() {
self.ended = true;
Some(self.slice)
} else if let Some(p) = self.slice
.windows(self.needle.len())
.position(|w| w == self.needle) {
let item = &self.slice[..p];
self.slice = &self.slice[p + self.needle.len()..];
Some(item)
} else {
self.ended = true;
let item = self.slice;
self.slice = &self.slice[self.slice.len() - 1..];
Some(item)
}
}
}
fn split_subsequence<'a, 'b, T>(slice: &'a [T], needle: &'b [T]) -> SplitSubsequence<'a, 'b, T>
where T: 'a + 'b + PartialEq
{
SplitSubsequence {
slice: slice,
needle: needle,
ended: false,
}
}