nested struct in solidity

Question

Can someone help me with a nested struct, I am unable to map the nested struct. I need to get into a struct some user details like name, gender, etc., and the user's home address as well, I tried the following but did not get anywhere:

struct Pdetails {
    
    string fName;
    string lName
    int256 age;
        enum gender;
    }

struct Addr{
    
    string line 1;
    string line 2;
    string city;
    string state;
    int256 pincode;
    }

---

function createUser(address _userAddress, uint256 _userId, string _fName, string _lName, int256 _age, enum _gender, string _line1, string _line2, string _city, string _state, int256 _pincode  ) public {
    User storage user = users[_userAddress];
    require(!user.set);
    
    //Store the user
    users[_userAddress] = User(
        {
        id: _userId,
        first_name: _fName,
        last_name: _lName,
        age: _age,
        gender : _gender,
        Addr line1: _line1,
        Addr line2: _line2,
        city: _city,
        state: _state,
        pincode: _pincode
        
        set: true
    }
    );
}
i tried to map these but i dont think this is the right way to do it

Answer 1

You can combine both of the structs into a new struct to store the information of the user. for example:

pragma solidity 0.8.2;

contract PersonalInfo{
    
    enum gender {MALE, FEMALE}
    
    struct Pdetails {
    
        string fName;
        string lName;
        int256 age;
        gender Gender;
    }
    
    struct Addr{
    
        string line;
        string city;
        string state;
        int256 pincode;
    }
  
    struct UserInfo{
        
        Addr addr;
        Pdetails pdetails;
    }
}

Answer 2

1. As it was mentioned in the first answer, It is easier if you combine your structs into one:

enum Gender{MALE, FEMALE}
    // Returns uint
    // MALE  - 0
    // FEMALE - 1
    
    struct Pdetails {
        string fName;
        string lName;
        int256 age;
        Gender gender;
    }
    
    struct Addr{
        string line;
        string city;
        string state;
        int256 pincode;
    }
  
    struct UserInfo{              
        Pdetails pdetails;
        Addr addr;
    }

2. Now regarding the mapping, you will have to have an elementary type (int, string, etc...) to be used as key, the value however can have any type:

mapping(key => value) mapName

In this case, I added another global variable called id, and by doing so, you can look for a person by his/her id. Your new combined struct will be this:

struct UserInfo{              
        Pdetails pdetails;
        Addr addr;
        uint id;
    }

Your map will be this:

mapping(uint => UserInfo) idToUserInfo

Now sum it all up:

pragma solidity ^0.8.10;

contract Struct {

    enum Gender{MALE, FEMALE}
    // Returns uint
    // MALE  - 0
    // FEMALE - 1
    
    struct Pdetails {
        string fName;
        string lName;
        int256 age;
        Gender gender;
    }
    
    struct Addr{
        string line;
        string city;
        string state;
        int256 pincode;
    }
  
    struct UserInfo{              
        Pdetails pdetails;
        Addr addr;
        uint id;
    }

    mapping(uint => UserInfo) idToUserInfo;

    function get(uint _id) public view returns (UserInfo memory) {
        return idToUserInfo[_id];
    }

    function set(Pdetails memory _pDetails, Addr memory _addr, uint _id) public {
        idToUserInfo[_id] = UserInfo(_pDetails, _addr, _id);
    }

}