General Thread For Practicing Question Formatting

[AmarRam90]

    function FUND() public
    {

        if( msg.value.GET_CONVERSION_RATE(  ) < MINIMUM_USD )
        {

            revert VALUE_NOT_ENOUGH(  );

        }

        FUNDERS.push( msg.sender );

        ADDRESS_TO_AMOUNT_FUNDED[ msg.sender ] = msg.value;

    }

On this function, I'm running into an error:

TypeError: "msg.value" and "callvalue()" can only be used in payable public functions. Make the function "payable" or use an internal function to avoid this error.
  --> contracts/FundMe.sol:51:13:
   |
51 |         if( msg.value.GET_CONVERSION_RATE(  ) < MINIMUM_USD )
   |             ^^^^^^^^^

Can someone tell me what's going on?

[gyane14]

Use the payable keyword for functions that are using "msg.value" or "callvalue()".

    function FUND() public payable {

        if( msg.value.GET_CONVERSION_RATE(  ) < MINIMUM_USD ) {
            revert VALUE_NOT_ENOUGH();
        }
        
        FUNDERS.push( msg.sender );

        ADDRESS_TO_AMOUNT_FUNDED[ msg.sender ] = msg.value;
    }