fnis_copy<T: Copy>() {}fntypes_impl_copy_trait() { is_copy::<bool>(); is_copy::<char>();// all iXX and uXX, usize/isize, fXX implement Copy trait is_copy::<i8>(); is_copy::(); is_copy::(); is_copy::<usize>();// function (actually a pointer) ...
// error:the trait `Copy` may not be implemented for this type // because its nums field does not implement `Copy` #[derive(Copy, Clone)] struct Numbers { nums: Vec<i32> } 当然,你也可以手动实现 Copy 和 Clone: struct Point { x: i32, y: i32, } // marker trait implCopy for Po...
Compiling rust-boom v0.1.0 (/Users/wmc/workspace/rust-boom) error[E0382]: borrow of moved value: `a` --> examples/move_copy_clone.rs:16:27 | 13 | let a = String::from("hello"); | - move occurs because `a` has type `String`, which does not implement the `Copy` trait 14 ...
3 |lets1 = String::from("hello"); | -- move occurs because `s1` hastype`String`,whichdoes not implement the `Copy` trait 4 |lets2 = s1; | -- value moved here 5 | 6 | println!("{}, world!", s1); | ^^ value borrowed here after move | = note: this error originatesinth...
moveoccurs because `string_obj` hastype`String`, which does not implement the `Copy`trait 在值对象的示例中,并没有这样的错误,也由此可推断值对象是实现了Copy Trait的,并且在作用域切换的场景中,直接使用Copy,在官方文档中,关于Copy特别说明了是简单的二进制拷贝。
moveoccurs because `string_obj` hastype`String`, which does not implement the `Copy`trait 在值对象的示例中,并没有这样的错误,也由此可推断值对象是实现了Copy Trait的,并且在作用域切换的场景中,直接使用Copy,在官方文档中,关于Copy特别说明了是简单的二进制拷贝。
types_impl_copy_trait里的类型都是实现了Copy trait的。 代码语言:javascript 代码运行次数:0 复制 代码运行 fn is_copy<T:Copy>(){}fntypes_impl_copy_trait(){is_copy::<bool>();is_copy::<char>();// all iXX and uXX, usize/isize, fXX implement Copy traitis_copy::<i8>();is_copy::(...
然后继续编译,继续出现错误提示,大致意思是说T还需要实现Copy trait: move occurs because`item`hastype`T`,which does not implement the`Copy`trait|help:consider removing the`&`:`item` 直接修改代码加上Copy 这个接口试试: fnmain(){// 定义一个整数数组序列letarr1=[1,2,3,4];// 定义一个字符数组...
结构可以是Copy,而i32是Copy,因此Point有资格成为Copy。相比之下,考虑 structPointList{points: Vec<Point>, } 结构PointList无法实现Copy,因为Vec<T>不是Copy。如果我们尝试派生Copy实现,我们会得到一个错误: the trait `Copy` maynotbe implementedforthistype; field `points` doesnotimplement `Copy` ...
| -- move occurs because `v1` has type `Vec<&str>`, which does not implement the `Copy` trait 9 | let v2 =v1; | -- value moved here 10 | println!("{:?}",v1); | ^^ value borrowed here after move | v1 拥有堆上数据的所有权。(每次只能有一个变量对堆上数据有所有权) ...