TypeError: Operator == not compatible with types function () view external returns (address) and address

Question

I am trying to read an address parameter in contract B from contract A and assert equality, but i get a type error:

TypeError: Operator == not compatible with types function () view external returns (address) and address

code:

contract A{
    ...
    function confirm(B _address) public returns(bool){
        B b = b(_address);
        require(b._addr == msg.sender);
        return true;
    }
    ...
}
contract B{
    address public _addr;
    ... 
}

Thank you very much :)

Answer 1

Variables behave like functions from the perspective of other contracts.

The error is telling you that b._addr is not an address, but a function that returns an address.

In contract A, try doing b._addr() instead of b._addr

Answer 2

Adding to @Jesse Busman 's answer, the methods of an address will also be available after calling the variable as a function:

contract B {
    address public owner;
}

contract A {
    B public b;

    constructor(B _contract) public {
        b = _contract;
    }

    function myTransferMethod() public {
        b.owner().transfer(msg.value);
    }
}