1, a default value is assigned to the stack memory, by packing Box partitioned heap memory
2, Box is a pointer to the type of smart memory allocation value T of the stack.
3, Box over scope, its destructor is invoked, deleting its internal object, automatically release the heap memory.
4, the character is acquired by dereferencing Box
. 5, Box acts as a reference, it can be automatically released.
fn main() {
struct BookInfo{
name:&'static str,
price:f32,
count:i32,
}
impl BookInfo{
fn print_book_info(&self){
println!("{}:{} {}",self.name,self.count,self.price);
}
}
let book1=Box::new(BookInfo{name:"C++模式",price:39.12,count:7});
let unboxed_book:BookInfo=*book1;
unboxed_book.print_book_info();
}
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `F:\learn\rustlearn\learn50\target\debug\learn50.exe`
C++模式:7 39.12
------------------
(program exited with code: 0)
请按任意键继续. . .
