I'm trying to run my code but I get this error:

Could not compile the source code.

Undeclared identifier. require(available); ^-------^ However, I defined 'available' as a boolean in a struct

struct Car{
  address  VechileOwner;
  string make;
  string model;
  Renter renter;
  bool available;
  uint pricePerDay;
  uint deposit;
  uint entrycode;
  uint minRentalDay;
  uint maxRentalDay;

Much Appreciated.


The correct way to use variable (or boolean) inside the struct in example:

pragma solidity ^0.4.18;

contract Car {

    struct car {
      bool available;

    car audi;

    function Car() public {
        audi = car(true);

    function checkAvailability() public view returns (bool) {

As you can see, you cannot just use require(available);; you need to assign the struct as some_name and then use require(some_name.available).

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