A helper macro to create closures which will clone its environment.
Use @var to clone a variable. Use @mut var to clone a mutable variable.
E.g.:
rust
cc!(|@a, @mut b, c, &d, mut e, &mut f| { a + b + c + d + e + f })
will be translated to:
rust
{
let a = a.clone();
let mut b = b.clone();
move |c, &d, mut e, &mut f| { a + b + c + d + e + f }
}
```rust use clonesure::cc;
fn main() {
// cc will implicitly move its environment
let s1 = String::from("111");
let s2 = String::from("222");
asserteq!(
// implicitly move s1 into the closure
cc!(|| format!("{}", s1))(),
"111"
);
asserteq!(
// explicitly move s2 into the closure
cc!(move || format!("{}", s2))(),
"222"
);
// clone one var let s1 = String::from("111"); asserteq!( // clone s1 into the closure cc!(|@s1| format!("{}", s1))(), "111" ); asserteq!( s1, // the original s1 is still alive "111", );
// clone many vars let s1 = String::from("111"); let s2 = String::from("222"); assert_eq!(cc!(|@s1, @s2| format!("{} {}", s1, s2))(), "111 222");
// clone var mut let s1 = String::from("111"); let s2 = String::from("222"); assert_eq!( cc!(|@mut s1, @s2| { s1 = s1 + &s2; format!("{}", s1) })(), "111222" );
// with closure params let s1 = String::from("111"); let s2 = String::from("222"); let s3 = 333; let s4 = 444; let s5 = 555; let mut s6 = 666; assert_eq!( cc!(|@mut s1, @s2, s3, &s4, mut s5, &mut s6| { s1 = s1 + &s2; s5 = 5000 + s5; format!("{} {} {} {} {}", s1, s3, s4, s5, s6) })(s3, &s4, s5, &mut s6), "111222 333 444 5555 666" );
// the order of cloned vars doesn't matter // the order of closure params will be keeped let s1 = 111; let s2 = String::from("222"); let mut s3 = 333; let s4 = String::from("444"); let s5 = 555; let s6 = String::from("666"); let s7 = 777; assert_eq!( cc!(|s1, @s2, &mut s3, @mut s4, &s5, @s6, mut s7| { s4 = s2 + &s4 + &s6; s7 = 7000 + s7; format!("{} {} {} {} {}", s1, s3, s4, s5, s7) })(s1, &mut s3, &s5, s7), "111 333 222444666 555 7777" ); } ```