关于

obstruct 是Rust的匿名结构体和命名参数的一个实验性实现。

匿名结构体

使用 instruct! 创建匿名结构体，并使用 destruct! 解构它

#![feature(associated_const_equality)]
use obstruct::{instruct, destruct};

// Create an anonymous struct.
let structured = instruct! { red: 0, green: 1.0, blue: 2 };

// Destructure that struct.
destruct! { let {red, green, blue} = structured };
assert_eq!(red, 0);
assert_eq!(green, 1.0);
assert_eq!(blue, 2);

注意，这不仅仅是一个元组：字段指定的顺序并不重要！

#![feature(associated_const_equality)]
use obstruct::{instruct, destruct};

// Create an anonymous struct.
let structured = instruct! { red: 0, green: 1.0, blue: 2 };

// Destructure that struct.
destruct! { let {blue, green, red} = structured };
assert_eq!(red, 0);
assert_eq!(green, 1.0);
assert_eq!(blue, 2);

如果你尝试访问一个不存在的字段，你将得到一个编译时错误

#![feature(associated_const_equality)]
use obstruct::{instruct, destruct};

// Create an anonymous struct.
let structured = instruct! { red: 0, green: 1.0, blue: 2 };

// Destructure that struct.
destruct! { let {blue, green, oops} = structured };
//                            ^^^ --- will fail with a complex error message pointing at `oops`.

命名参数

使用 destruct! 创建接受命名参数的函数，并使用 call! 调用它

#![feature(associated_const_equality)]
use obstruct::{call, instruct, destruct};

// Create a function accepting anonymous arguments.
destruct!(fn do_something({red: u8, green: &'static str, blue: ()}) {
    println!("Roses are {red}");
});


// Call this function
call!(do_something, {red: 0, green: "GREEN", blue: ()});

// Or equivalently
do_something(instruct! {red: 0, green: "GREEN", blue: ()});

再次强调，参数指定的顺序并不重要

#![feature(associated_const_equality)]
use obstruct::{call, instruct, destruct};

// Create a function accepting anonymous arguments.
destruct!(fn do_something({red: u8, green: &'static str, blue: ()}) {
    println!("Roses are {red}");
});

do_something(instruct! {blue: (), green: "GREEN", red: 0});

再次强调，错误在编译时会被捕获

#![feature(associated_const_equality)]
use obstruct::{call, instruct, destruct};

// Create a function accepting anonymous arguments.
destruct!(fn do_something({red: u8, green: &'static str, blue: ()}) {
    println!("Roses are {red}");
});

do_something(instruct! {blue: (), green: "GREEN", oops: 0});
//                                                 ^^^ --- will fail with a complex error message pointing at `oops`.


call!(do_something, {red: 0, green: "GREEN", oops: ()});
//                                           ^^^ --- will fail with a complex error message pointing at `oops`.