我正在阅读的代码包含以下(略微更改)的RuST代码:
let new_var : Vec<...> = (0..1 << some_number)
.into_par_iter()
.map(...)
.collect();
I recognize that it iterates over a range and constructs elements of a Vec for each number.
But why does it bitshift the 0..1 range? What is the resulting iterator that gets iterated over?
左移运算符<< has higher precedence比范围运算符(..).因此，1 << some_number首先进行判断.
您还可以对以下代码使用招聘(High-Level Intermediate Representation) as an output mode in rust playground to see how rust compiler解析/生成招聘
fn main() {
let a = (0..1 << 2).into_par_iter();
}
招聘
#[prelude_import]
use std::prelude::rust_2021::*;
#[macro_use]
extern crate std;
fn main() {
let a = #[lang = "Range"]{ start: 0, end: 1 << 2,}.into_par_iter();
// ^^^^^^^^^^^
}