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Is there any connection between Serenity Market and Ethereum 2.0 (codename Serenity)?

From what I gather, no... Simply an exchange that's named the same? https://serenity.exchange/
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0answers
3 views

How to display formatted transaction information in Remix IDE from web3.eth.getTransactionReceipt()?

tl,dr: Remix shows a formatted transaction summary for transactions that are initiated within the Remix IDE. Is it possible to display the same output for an arbitrary transaction hash? Sorry if this ...
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1answer
3 views

MEW keeps putting in QSP contract address for receiver instead of address I've entered

I'm trying to send Quantstamp (QSP) to Binance offline, using MyEtherWallet. In mew's offline helper... when I paste in the signed transaction (into the online MEW, as received by offline version of ...
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0answers
8 views

Private Ethereum as private payment system

Case This is a hypothetical question. Let us assume we own a group of stores, restaurants or cafes and want to give our customers the opportunity to pay per App, with our own system not an external ...
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0answers
5 views

any one please help when show QR for receiving erc20 token

any one please help when show QR for receiving erc20 token can i enter amount like "ethereum:ethaddress?address=contractaddress&uint256=token" not working "ethereum:...
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0answers
6 views

What was the Rebase Bug on the YAM smart contract?

Smart contracts have great power to absorb money like a black hole. Almost 400$ Million is gone due to a bug in the smart contract of YAM. What was the bug that cause all the destruction? => Could ...
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1answer
7 views

How to deploy smart contract using Remix 0.8.0 and MetaMask?

How do I deploy a contract on a test network using Remix 0.8.0 and MetaMask on a Firefox or Chrome browser?
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0answers
19 views

Node version upgrade for contract deployment throws error

I wrote a solidity contract using version 0.4.24 using OpenZeppline-solidity version 1.12.0. This used to deploy using the Nodejs version 8.12. The Nodejs version 8 is no longer being maintained from ...
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0answers
19 views

Is first call to oraclize query free in mainnet, as in testnet?

We were trying to include oraclize query to get price feed in one our contracts, as of now we have observed that the first oraclize is free in kovan. Does same applies for mainnet or else we has to ...
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0answers
11 views

Subscribing to new blocks doesn´t work [ROPSTEN]

I'm trying to subscribe to newBlockHeaders on the ropsten network, but it does not seem to work. The following code works for mainnet but not ropsten. Any ideas? const Web3 = require('web3') const ...
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0answers
5 views

Has anybody used Atomic Wallet for cold storage?

Interested to know if anybody has used this application in an offline setting.
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1answer
14 views

How to programatically change the current network with MetaMask

I would like to have a button that switches between main net and ropsten on my app, in order to do so I need to programatically change the current network with MetaMask. But I cannot find aby ...
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2answers
14 views

Truffle not deploy updates

Truffle not deploy contract updates. truffle migrate compiles it but falsely say network up to date. OS: Windows Truffle v5.1.39 npm 6.14.5
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1answer
19 views

How to send erc20 token with web3 without smart contract abi?

I created a token in the Ropsten network. It wants abi.json when transferring with Web3. But the token I created did not give it. My token etherscan link https://ropsten.etherscan.io/address/...
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1answer
17 views

How to create forwarder wallet in Ethereum?

I have more than one ETH wallet. I want to automatically combine these wallets into one wallet. For example, when I get an ETH in wallet 0x1, I want it to automatically transfer it to wallet 0x2. Can ...
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0answers
6 views

Pending Ethereum transaction on smartrix

Good evening. I registered on smatrix and I upgraded my first level 40hrs ago and my Eth was deducted. Yesterday, I checked my account ....then I saw 0payment sent but my 0.02 ethereum was deducted . ...
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0answers
17 views

Supply chain asset exchange

I'm trying to create a supply chain example using solidity. This is the part of the code where I create an raw material asset (rawMaterial contract) and transfer it to the next company in the supply ...
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1answer
19 views

Go-Ethereum EstimateGas - Error: VM Exception while processing transaction: revert

Been struggling in finding a way to estimate gas for calling a function. Here's a sample solidity function: This is what my code looks like: sig := []byte("withdraw(address)") methodID := ...
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0answers
21 views

Transaction reverted but not refunded

My transaction https://etherscan.io/tx/0xd4f9905b14e26ee96b243f47e734e1b7880dc2a23f8f847dae786fca0f3f9888 has failed and was marked as reverted 15 hours ago. Though i don't think my ETH wallet has ...
0
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1answer
19 views

Hello i am te admin of the discord o f the eth black smart contract the site got suspended what now

Heeey superstars thank you for taking the time to answer this question Me and my people are in the eth black smart contract but the site got offline is there anything we can do to get our money our ...
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1answer
10 views

Truffle re-deploy unchanged contracts on every migrate

On every truffle migrate truffle deploy contracts even if they are not changed. although it doesn't re-compile Truffle v5.0.5
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0answers
14 views

Prevent opening metamask on ethereum.enable/creating new web3 instance

How can I prevent initializing Metamsk on window.ethereum.enable() or on creating a new instance of Web3?
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0answers
12 views

Time-dependent tests with Buidler?

For Ganache, there are several solutions. What about Buidler? They implemented their own local blockchain, buidlerevm, which is different to Ganache.
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1answer
10 views

Why is the receive () external payable not acting as a fallback?

I have this simple code in remix.ethereum pragma solidity ^0.6.1; contract SimpleWallet { address owner; constructor() public { owner = msg.sender; } modifier ...
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1answer
20 views

Cannot read data from smart Contract with web3 js

Im having trouble reading data from a smart contract I have following js script right here: (bcc-js.js) var contract_address = "0x88e304D8638c31DaC3336917bbE4A152927198D8"; var contract_abi =...
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0answers
5 views

What is the expected daily egress traffic from full Testnet node

I have a full testnet node running on GCP with Parity. After about a week of having it fully synced, the egress traffic from the server spiked substantially and started sending out 250GB per day to ...
0
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1answer
18 views

Interacting with Bytecode

Is it possible to interact with a smart contract with bytecode only (without ABI)? If yes, how can I do this?
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0answers
8 views

Read ABI directly from network api in GOLang

Using go-ethereum package how can we read the JSON file of the deployed contract and then get the ABI out of it and then instantiate? I don't want to compile smart-contracts into GO but want to use ...
1
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0answers
12 views

Why does ethereum chaindata sometimes sync while syncing?

I am doing a fresh geth 1.9.18-stable sync, which I believe is fast by default. I am keeping an eye on the size of the .ethereum/geth/chaindata/ directory and have noticed that it does not increase ...
0
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1answer
25 views

What happens if two different states of smart contract conflict?

I'm newbie studying blockchain and Ethereum. While I'm studying, I've got a question. What will happen in the case of conflict of two different states on smart contract, e.g. from the network ...
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0answers
8 views

Error when recalling smart contract using code; todoList = await TodoList.deployed() [closed]

When I try to recall the contract after it has been successfully deployed, I type the following code: todoList = await TodoList.deployed() ReferenceError: TodoList is not definede console at ...
1
vote
1answer
8 views

State Changes within a Block

I read somewhere that the 'state' is only updated at the end of each block. I've also read that each block contains a specific sequence of transactions, and thus implicitly 'updates' the state within ...
1
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0answers
12 views

What is the method to send a transaction with data from solidity?

Sorry for the noob question, but Im trying to understand some definitions and clarify the limits between solidity, web3, etc. I have obtained a tx looking like the following from the 0x API: b'{"...
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1answer
18 views

What does this piece of code mean?

Can you tell me what this piece of solidity code means please? uint number = uint(block.blockhash(block.number - 1)) % 37; Thank you Take care Pierre
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1answer
8 views

Connect web3.py with Ganache

I am new to this. So, how do I connect web3.py with Ganache. I've got Ganache up and running, smart contract deployed. I would like to interact with it from, lets say, a python shell. So, this is what ...
0
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0answers
14 views

I accidentally sent a token to a token contract. Can I get it back? $YFI

Instead of transferring my ERC20 token to my wallet, I accidentally sent it to the contract itself(Here is source code https://etherscan.io/address/0x0bc529c00C6401aEF6D220BE8C6Ea1667F6Ad93e#code) ...
2
votes
1answer
9 views

How can I use “@” (at sign) syntax with Remix?

I've seen multiple times Solidity contracts, which are using import "@somename/.../SomeContract.sol" syntax. Here's the example: pragma solidity ^0.5.0; pragma experimental ABIEncoderV2; ...
0
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1answer
6 views

How many parallel read/write request single contract can handle each second

I need this reply for a large user base prospective, where each second too many request going to that particular contract , so the question is what is write per second limit and what is read per ...
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0answers
23 views

What do you think about eth 2.0? [closed]

What are you expecting from ETH 2.0? Are you going to use it? According to this article - https://medium.com/the-capital/ethereum-2-0-why-the-transition-is-painful-and-risky-ca0ec12305b3 there Shouldn'...
0
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0answers
7 views

I've got a problem with the id search function and it displays the following error “Error: hex data is odd-length ”

$("#searchBtn").click(function () { patienttdetailsContract.methods.readPatient(parseInt($("#p_search").val())).call(function (err, result) { console.log(...
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0answers
33 views

Tax coins for Universal Basic Income

I am working on building a coin that will be useful in providing UBI, but need a method to maintain the price of the coin, so that it doesn't fall below threshold. Here is the idea: So every month, ...
0
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0answers
6 views

Can you use biconomy or GSN to pay for gas when deploying a contract?

I'm building a small dapp to allow users to deploy smart contracts without needed gas, where I'll use GSN or biconomy. I'm not sure you can use meta-transaction services like these for transactions ...
0
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0answers
7 views

Unable to connect to Geth/web3 from outside AWS using public IP with Websocket

I tried RPC api to connect to Geth/web3 hosted in AWS EC2 using the public IP. But developers have disabled web3 in RPC(HTTP) Web3 api for non local connection. It means that you can only make a web3 ...
0
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1answer
18 views

Truffle test. Convert '0x0000000000000000' to zero. Assert it doesn't exist [duplicate]

I am writing a truffle javascript test and I need to test if a key in a mapping was deleted. After deleting it, its values are equal to '0x0000000...' . How can I test in a truffle javascript test ...
1
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0answers
4 views

Fatal: Error starting protocol stack: gap — Chain freezer table opened

I started to get following error: Fatal: Error starting protocol stack: gap (#3697270) in the chain between ancients and leveldb. What may be the cause of this error? I was able to fix it by syncing ...
1
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0answers
31 views

Execution erorr: Invalid opcode on estimateGas | Possible unhandled promise rejection

pragma solidity ^0.5.0; I get invalid opcode error when trying to estimate gas needed for my transaction from react-native using the following line of code: const gasAmount = await contract.methods ...
1
vote
1answer
28 views

Recovered address not matching signer address (using ethers)

Below is a simple signature verification flow I wrote, along with a test case with Buidler (all mainly to learn how to verify signatures in a Solidity smart contract). The problem is that the address ...
0
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0answers
22 views

Why are there errors in the code I copied in a book called Ethereum smart contracts development”

pragma solidity ^0.4.11; contract simpleVotingDapp { /* The key of the mapping is candidate name stored as type bytes32 and value is an unsigned integer to store the vote count */ mapping (bytes32 =&...
0
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1answer
10 views

Can not Open Ethereum Wallet on Window 10

I did trying install soft Ethereum wallet on windows 10, But I can't open the program. It looks like the picture below. Help me pls, Thank everyone.
1
vote
2answers
33 views

In assembly… can't get delegatecall to work

Delegatecall can be used in either solidity or assembly. In solidity, I can get it working with the following code: bytes memory payload = abi.encodeWithSignature ("get_value(uint16,uint16)",...

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