json - cannot move out of dereference -

i'm learning rust extra::json module. here example (with unneeed type annotations):

let j:result<json,jsonerror> = from_str("[{\"bar\":\"baz\", \"biz\":123}]"); let l:list = match j {   ok(list(l)) => l,   ok(_) => fail!("expected list @ top level"),   err(e) => fail!(fmt!("error: %?", e)) }; println(fmt!("item = %?", l.iter().advance(|i|{   match {       &object(o) => {           println(fmt!("object %?", o));       },       _ => {           fail!("should list of objects, no?");       }   }   println(fmt!("i=%?", i));   true }))); 

when compile, this:

$ rust run json.rs json.rs:70:9: 70:18 error: cannot move out of dereference of & pointer json.rs:70         &object(o) => {                     ^~~~~~~~~ note: in expansion of fmt! json.rs:68:10: 79:6 note: expansion site error: aborting due previous error 

i have other examples of using match don't hit error.

thanks help!

patterns destructuring, means move out of thing match on default. want:

&object(ref o) => { ... } 

which takes borrowed reference member, rather moving out of it.