Lesson 3 (FundMe): why is withdraw() payable?

[xavierdmello]

I've tried it both ways, and it doesn't seem to matter if it's payable or not. Just curious why withdraw was payable in the tutorial. Was it just an oversight?

[cromewar]

Hello @xavierdmello
The reason si because you are transferring Ethereum to the msg.sender.

As you are transferring the balance of the contract, the function is payable as you are "paying" to the wallet which si doing the withdraw.

[xavierdmello]

Thank you. Since the user never sends any ether to withdraw(), would it still need to be payable? Or is it just good practice etc.

[cromewar]

Yeah, the one which sends the payment is the contract so the address should be payable and in consequence de function as well.