Hey devs, can someone help me with implementing a stuct within a struct. I seem to be missing something.

I have 3 structs. A, B, and C.
A can have zero to many B's,
B can have zero to many C's.

struct A {
B[] b;
string fields;
}

struct B {
C[] c;
string fields;
}

struct C {
string fields;
}

mapping (address => A) internal a;
[I think over here I'm missing a link between B and C]

Problem: I can insert into A successfully (without having to send a B), but when I try and insert into B then it says it's missing a field (which is C)
#hopethatexplainsit

Show code and corresponding error. Also, can't you access it like
a[address].b[index].c[index]

what are you doing?

Working fine for me.

B newB = B({
c: [C({fields: "some value for fields in C"})],
fields: "some value for fields in B"
});.. try to fake it with empty values i do not get you

In Solidity, fields in a struct are required unless you specify a default value for them. For example:

struct Example {
uint256 a;
uint256 b;
string c;
bool d = false;
}

Example example = Example({a: 123}); // Error: missing field b

hope this help... hit inbox we discuss more if needed..

contract A {
address public contractB;
constructor(address _addr){
contractB = _addr;
}

function deposit() public payable {
}

function withdraw() public {
uint bal = 1 ether;
payable(contractB).transfer(bal);
}
}

contract B {
uint public count;
fallback() external payable {
if (count<=5) {
count++;
}
}
}


Why Txis failing in the following scenario:
1. Deploy contract B.
2. Deploy contract A by passing the address of contract B.
3. Deposit some ether to contract A using the deposit function. (Deposite more than 1 ether).
4. Calling withdraw function. Here Tx is failing. Why?

I think your fallback costs more than 2300 gas

due to the fact that you added calculations to it

use contractB.call{value:1e18}("") and add success check

If I don't do calculation, just assign some value such as count =1 , still this is not working.
Is there any restriction of gas uses in fallback function?, even I can do the same thing through call low level function, then there is no problem with gas. Why?

use low level call

Yes I can do, I am not doing project 🤣🤣. I am just experimenting. So I want to do this by transaction function

The restriction is on the .transfer you are using to send eth.

It have a hardcoded 2300 gas limit, which doesn't allow any fallback/functions to execute

Ohh. Thanks. Can you send me link of this concept from solidity documentation. I tried but didn't find this becuz I have also tried to debug it on remix , there was some gas problem.

Let me research again on documentation

Search for solidity transfer function

Got it. Thanks

https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/

Any yul masters in here?

I think we need a community😅

What’s the ideal?

Wdym?

Man, you don't have receive() function in contract B. Its basic knowledge. Contract B can't receive payments without this.

It can

Well, fallback() CAN receive Ether.

LOL

"basic knowledge"

Suppose you send a transaction with a missing function signature.

Then it would be handled by fallback(), and as it's payable here, Ether reception would also be handled just fine.

yeah, my bad. Fallback payable gives opportunity to receive ether. hmmm

Nice.

it's weird practice, but it's works.

Folks, I'm not sure if it's for you, but would you like to become better solidity devs? Obviously, yes. So join the party and start studying Yul 🔥🔥🔥

https://t.me/yul_eth

pure fallback can't

where you test this code? In Remix ide?

Yes

What's yul

Yul is a low-level assembly language,
You can use it to optimize the code for cheaper gas usage or call low level functions.

Credit to @StevengrantANT🙏

Just saw. Thanks
But how do you integrate another language to Solidity?

Solidity supports assembly, it all gets compiled into bytecode at the end of the day

I have question guys do you all master or feel comfortable with other languages or framework? Are you specialized in solidity or you are able to do full stack?
It is just curious question as I'm trying to learn next js now and kind see the way long 😅
I mean learning solidity alone can be fast but with all the things around 😅.. Make the learning process kind long

Same same. I started with js then react then solidity. Now I went back to learn nodejs and mongo cause it’s good to know some full stack like MERN but I think there is so much more to solidity than just making tokens or nfts. Solidity by itself is a huge world.

I feel pretty powerful only with solidity/Js/python or at least, there isn't anything i could not do with those.
Of course having a background in IT/servers in general is a plus, as you can configure whole backends from scratch (even if sometimes using hosted solution like AWS maybe it's more safer for certain things)

Exactly

100%, since i saw foundry & solidity scripting/tests, I've revaluated solidity 😂😂

https://github.com/memester-xyz/surl

Anyone have any idea why the withdrawal function reverts

Yeah I just went back to web2 stuff in case the market gets worse I can get a web2 job in the meantime. Ultimately I wanna do solidity. So much I wanna learn about it and so little time

Answer is already revealed above,

Can you direct me to it

web3 jobs lost volumes, as the whole market.
This give you time to learn all the web2 things you miss but don't get too easy, once the volumes kicks back in, who got more exp on web3 will have good time

Read chats from here.

kiki

Thank you all, this is real encouragement, I really appreciate it 🙏

Oh bro I ask this on discord as well . 🤣🤣

That's where I saw it

I ask the same question here as well.

What's about the foundry and Solidity scripting/tests that made you reevaluate Solidity?

This HTTP library can query data from like an API?
Directly into a smart contract??
Damn 🤩

You can see

You cannot change them in memory, cause there is no dynamics in there.

Yeah. That's how I did mine too

Thanks Viktor 👏🏼

yep, but only in localhost of course :P

That's useless then ☹️

a phrase from someone that has a closed mind

Well, at the moment I mean

It would be put to greater use it in a production app

😒😒

no black magic

you can send a telegram message with the deployed address directly within a solidity contract

seems useful to me :o
i had a little snippet to do that in js, seems it's possible in solidity /w foundry, with that library

no bot.send_message tho, raw post api call

lol

Submitting the API token in a transaction or so 😄

bruh

it's on localhost

evm cannot access internet

Connecting web2 with web3 infrastructur is always stupid

it's an "hack" i guess, won't work on real networks

I mean we store some stats aswell in a database, but why using a database local

depend on what you need to build

Right now encrypting data on transaction is kinda expensive and "unsafe"

I mean if someone gets your RSA Private key, he can decrypt all messages ever been

No deleting 😂

For speed a regular PSQL database is useful

OneTimePad would be an option😄

Working on idea of having an encrypted system which has the data on the blockchain, so nobody can intercept the database or delete smth

But biggest issue is solving private key issue 😄