// First, we declare a type which has the `iter` method to get the `Iter` // struct (`&[usize]` here): let slice = &[1, 2, 3]; // Then, we get the iterator: let mut iter = slice.iter(); // So if we print what `as_slice` method returns here, we have "[1, 2,...
本文简要介绍rust语言中 std::cell::Cell.as_slice_of_cells 的用法。用法pub fn as_slice_of_cells(&self) -> &[Cell<T>] 从&Cell<[T]> 返回&[Cell<T>] 例子 use std::cell::Cell; let slice: &mut [i32] = &mut [1, 2, 3]; let cell_slice: &Cell<[i32]> = Cell::from_mut(...
fni_to_str(&self, i: int)->&'astr{returni.to_string().as_slice(); } This code is producingerror: borrowed value does not live long enoughbecause of as_slice lifetime. Does anyone knows is there some workaround for this to make this possible?
ptr = alloc::realloc(ptr as *mut u8, layout, 64 * mem::size_of::<i32>()) as *mut i32; let slice: &mut [i32] = slice::from_raw_parts_mut(ptr, 64); slice[0] = 123; slice[1] = 456; slice[2] = 789; println!("{:?}", &slice[..3]); // [123, 456, 789] // ...
as_slice(), b"value".as_slice())) } } } 这样一来,就可以通过编译了!随手实现一下 TestIterator 内部的逻辑: pub struct TestIterator { idx: usize, to_idx: usize, key: Vec<u8>, value: Vec<u8>, } impl TestIterator { pub fn new(from_idx: usize, to_idx: usize) -> Self { ...
fnprint_words(sentence:&str){letwords:Vec<_>=sentence.split_whitespace().collect();match words.as_slice(){[]=>println!("There were no words"),[word]=>println!("Found 1 word: {}",word),_=>println!("Found {} words: {:?}",words.len(),words),}}fnmain(){print_words("");pri...
rust另一种不持有所有权的数据类型:切片(slice) 从一个例子开始:实现一个函数,输入一字符串,返回该字符串第一个单词,如果没空格,则返回整个字符串。 第一种实现,先返回找到的第一个空格的位置 fnmain() { lets= String::from("hello world");
NonNull::<[T]>::slice_from_raw_parts(data: NonNull<T>, len: usize) -> Self 将类型指针转化为类型的切片类型指针,实质是ptr::slice_from_raw_parts的一种包装。 NonNull::<[T]>::as_non_null_ptr(self) -> NonNull<T> const [T]::as_ptr的NonNull版本 ...
通过as 关键字,将 x 转成 u8 就没问题了。然后我们上面创建的整数都是十进制,如果在整数前面加上 0x, 0o, 0b,还可以创建十六进制、八进制、二进制的整数。并且在数字比较多的时候,为了增加可读性,还可以使用下划线进行分隔。fn main(){let x = 0xFF; let y = 0o77; // 数字较多时,使用下划线分隔 ...
letnums:Vec<u8>=vec![0,1,2,3];letslice:&[u8]=&nums[0..2]; The important thing to notice is "Slice doesn't own the elements, just references them". Full code of the Vec or String: nums.as_slice()strings.as_str() Example: ...