pub fn caller() -> Address {
    let mut addr: Address = Address::zero();
    unsafe {
        env::ontio_caller_address(addr.as_mut().as_mut_ptr());
    }
    addr
}
///return Caller's contract address
/// # Example
///
/// ```no_run
/// # use ontio_std::runtime;
/// let res = runtime::caller();
/// ```
///
return Caller's contract address
return Caller ' s contract address
pub fn caller() -> Address {
    let mut addr: Address = Address::zero();
    unsafe {
        env::ontio_caller_address(addr.as_mut().as_mut_ptr());
    }
    addr
}
pub fn caller ( ) -> Address { let mut addr : Address = Address :: zero ( ) ; unsafe { env :: ontio_caller_address ( addr . as_mut ( ) . as_mut_ptr ( ) ) ; } addr }
return Caller's contract address
return Caller ' s contract address
example
None
use ontio_std::runtime;
let res = runtime::caller();
```
let res = runtime :: caller () ; ` ` `