SOLANA - 如何检查链上的薄荷供应？

Question

folks, how do I check for the supply of a mint account on-chain? I have no idea on how to do this. I've tried using:

let mint = Mint::unpack_unchecked(accounts.mint.data).unwrap();

Then I get this error:

 expected reference `&[u8]`
      found struct `Rc<RefCell<&mut [u8]>>`

Also, in my function, if I try to get accounts.mint.data to &[u8] format by doing this:

let data = accounts.mint.data.borrow().as_ref();

I get this non-sense error:

consider using a `let` binding to create a longer lived valuerustcE0716
mod.rs(98, 64): temporary value is freed at the end of this statement
mod.rs(99, 51): borrow later used here

Answer 1

Nevermind:

let mint = Mint::unpack_unchecked(&accounts.mint.data.borrow()).unwrap();

to get the supply, just access mint.supply