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Contract ERC20 creation “pendond”

I have created a new ERC20 contract using this generator https://vittominacori.github.io/erc20-generator/ The status is "pending" , 21 hours at this time. Some explanation? Previously, I tried it ...
0
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1answer
8 views

Are the timestamps of blocks for Ethereum only accepted when they are monotonically increasing?

Are the timestamps of blocks for Ethereum only accepted when they are monotonically increasing? If yes, why? And why other blockchains like Bitcoin and other blockchains with shorter block time can ...
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0answers
9 views

How to define non-exploitability in the difficulty update algorithm?

In enter link description here, it is said that "We have already determined that our current algorithm is highly suboptimal on low volatility and non-exploitability, and at the very least we plan to ...
1
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0answers
16 views

Why creating a block that has slightly higher difficulty can beat out any possible forks?

It is said that "The use of (block_timestamp - parent_timestamp) // 10 (* now 9)as the main input variable rather than the time difference directly serves to maintain the coarse-grained nature of the ...
0
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1answer
13 views

Apparently some people send transactions with zero gas and positive gas limit, how do they do this? (and I am NOT planning to this but how)

Have a look at this transaction for example: https://etherscan.io/tx/0x11d96986d36240a5e5e7eab78879aa841631705370e707f15f1488a0b9d6704a 0 gas, 0 ether but plenty of tokens transferred. Obviously the ...
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0answers
8 views

ParserError: Expected pragma

Hi guys. I have got one big problem. When i try to compile my code i'm getting some kind of unusuall error. I think everything is ok but when i try to "node compile.js" my main file ("inbox.sol") ...
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0answers
7 views

How can I distribute funds to present stakers efficiently?

I am building a smart contract which keep the token holder's eths for a while and give them rewards when they withdraw. The reward is given from the ethers collected by early withdraw of people. If ...
0
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1answer
15 views

ERC20.balanceOf changes output without any Transfer events occurred

Here is a use case, There is an interest generating ERC20, where each address may have increasing balances for each blocks from earning interest. Usually, one would need to send a non-standard ...
0
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2answers
10 views

Why am I getting TypeError: Member “balanceOf” not found or not visible after argument?

On line 22 my code is -- require(tokenContract.balanceOf(this) >= _numberOfTokens); This gives the error message TypeError: Member "balanceOf" not found or not visible after argument-dependent ...
1
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1answer
8 views

AttributeError: 'Web3' object has no attribute 'middleware_stack

web3.py version: 5.0.1 , Python: 3.6.3 Following code was working on web3==4.9.2, which does not work for the web3==5.0.1. I am getting following error: web3.middleware_stack.inject(...
0
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1answer
20 views

Is it possible to send erc20 token when I have 0$ ether but $1000 in the token?

Long story short I have $1000 in one erc20 token contract but 0$ in ETH. Can I at least transfer these $1000 from the token to another address without ethereum asking for gas? That is: just change ...
1
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0answers
6 views

Transaction always failing - Vyper

I've been trying to teach myself how to program smart contracts in Vyper and I was trying out a toy problem where the contract transfers USDC to itself and then mints some Compound USDC on Compound ...
2
votes
1answer
11 views

How is the length of the message counted when calling eth_sign?

According to https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sign The sign method calculates an Ethereum specific signature with: sign(keccak256("\x19Ethereum Signed Message:\n" + len(message) +...
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0answers
10 views

Truffle deploying smart contracts to a private blockchain on a virtual machine (digital ocean)

I tried truffle deploying smart contracts to local geth private blockchain with success, but I cannot deploy the same contract to private blockchain(with the same genesis) on Digital Ocean droplet. ...
0
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0answers
8 views

How to connect to Rinkeby without using Geth / Parity?

First let me explain my development environment. I am using Jupyter Notebook to play around with the Web3.py front-end code and Remix for the Solidity smart contract code. I am using the Metamask ...
0
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1answer
8 views

Load Smartcontract in Nodejs

I created the server based on golang. This server can load smart contract that is deployed using its address. It works on my local machine, but it does not work on EC2 instance. So I decided to ...
0
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1answer
19 views

“onlyOwner” Function restrict the call from child contract

I have a basic knowledge of solidity. I am trying to create an upgradable ERC20 Token. For that, I create TokenStorage contract and Logic contract and trying to write the Proxy contract. In the Logic ...
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0answers
9 views

EIP712 implementation for web3 1.0

I tried replicating the instructions in this article to implement EIP712 signing, however, it doesn't appear to work for web3 1.0 versions. https://medium.com/metamask/eip712-is-coming-what-to-expect-...
2
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0answers
11 views

What is an SSZ partial?

What is an SSZ partial? What are its benefits and are there any existing similar concepts that would help in understanding it? Some references: https://github.com/ethereum/eth2.0-specs/pull/1184/...
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0answers
18 views

invalid JSON RPC when using custom domain name

geth --testnet --networkid 3 --syncmode "fast" --datadir "." --cache=2048 --rpc --rpcport 8545 --rpcaddr example.ropsten.hk --rpcvhosts example.ropsten.hk --rpccorsdomain "*" --rpcapi="web3,miner,...
2
votes
2answers
30 views

Why can't I use a contract method in my Chrome console?

I am attempting to call a method from a smart contract from my chrome console. My dApps index.html file is deployed locally at http://127.0.0.1:5500. I set up web3 and instantiate a smart contract ...
0
votes
1answer
23 views

Function should return all objects stored in the mapping array

Here's my solidity code. And I want all the objects to be returned stored in mapping array contracts in the getContract method by giving address as a parameter to the getContract function. pragma ...
0
votes
1answer
14 views

When calling a contract from an other contract, what happends if the value of callgas argument is above availaible gas?

In such case, the value is replaced with available gas right ? Or Does an out of gas exception is thrown ?
0
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2answers
28 views

How to get response from Solidity Smart contract by Web3 client?

Here is the Smart contract code. I want to get the result of function of UserRegister by using web3. function UserRegister(string memory userName,uint feiyong ) public payable returns(string ...
0
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0answers
11 views

Truffle migrations - get deployed contracts list

I have the following problem: migrations no. 7: (deploy proxies) await deployer.deploy(TestProxy); await ExportUtils.addDeployed(await TestProxy.deployed(), true, { privileges: [ { ...
0
votes
1answer
19 views

Decentralized database for ethereum?

I'm looking for a way to store data in a decentralized way such that I can access any record from within the smart contract, probably through oracles I guess? I've been looking into gundb but not ...
2
votes
0answers
17 views

What is SSZ SimpleSerialize and why was it developed?

We were looking at the latest spec and it didn't have much background information or explanation on what SSZ is trying to achieve. What are the key goals of SSZ? Examples of its serialization and ...
0
votes
1answer
30 views

Solidity: extract data from signed message?

In an effort to reduce gas costs for users, I'm looking for a way to delegate certain transactions to a contract owner so that the owner makes a transactions that would have been otherwise sent by the ...
0
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0answers
23 views

How can I use bitcoin block stamp as seed for random number generation?

I am trying to create an ethereum based smart contract that shall generate random number. After searching around, I get to know that ethereum block stamp is vulnerable to miners hacks and false ...
0
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0answers
7 views

How can I find the block where a user enacted a certain event on a contract?

I'm trying to build a web3.py program to take in a given user's address, and return the amount of ETH traded since they added liquidity to a Uniswap exchange. Uniswap is a smart contract on the ...
-2
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0answers
14 views

How do I get people to interact with my DApp? [on hold]

I am making a password recovery DApp on the Ethereum blockchain: https://cracknet.io It enables people to pay a reward to crackers for cracking cryptographic hashes via Ethereum smart contracts. The ...
0
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2answers
22 views

Remix Deploy Error encoding arguments

I'm building a simple fund raising smart contract and having problems deploying this through Remix. I'm wanting to set the "goal" and "minimum contribution" values (in wei) during the contract ...
0
votes
1answer
17 views

Is it possible to deploy the ERC721 token on private network for free?

I created a private network with 3 instances (one controller, 2 nodes) based on PoA on AWS. And I checked if my custom ERC721token is deployable by using Ropspan test network. so I have a working-...
0
votes
1answer
24 views

What is meant by a “non one time use EOA”

Could someone explain what is meant by a non-one-time-use externally owned account and what is used (or misused) for?
0
votes
1answer
22 views

TypeError: Cannot read property 'nodes' of undefined

I'm new to ethereum, and I'm trying to test the depositToken function of etherdelta on linux, which version is 0.4.9, and the token I use is vixcore which version is 0.4.24, and I got this error when ...
1
vote
1answer
38 views

Off-chain authorization system

I'm working on a dapp and am running into a dilemma regarding how to balance trustlessness with the cost of transactions for users. In order to reduce gas usage by users, I want to be able to able to ...
3
votes
2answers
34 views

Alternatives to metamask [on hold]

What are existing alternatives to metamask with that works online inside existing browsers, that don't require installing a browser extension? What are some of the tradeoffs between them?
1
vote
1answer
11 views

Uncaught (in promise) Error: Contract has not been deployed to detected network (network/artifact mismatch)

The client side application always throws the above error. I have connected the ganache account(by copying the private key)also with the correct port number in Metamask extension as well as in the ...
0
votes
1answer
17 views

Quorum Nodes not syncing

I have 5 nodes with quite different block numbers( one is stuck at 201504, another at 280432 and so on) , they don't seem to be syncing. No particular error in Quorum Logs as well. Any transaction ...
0
votes
0answers
10 views

How to filter by string parameter , web3 2.0.0-alpha.1 Solidity events?

I'm trying to filter some events , and I noticed since I updated the web3 to version 2.0.0-alpha 1 the event catch is a little bit different. I have a Smart Contract with this event : event ...
3
votes
0answers
21 views

account unlock with HTTP access is forbidden [duplicate]

I am using in the geth console and there is a similar error. Do I add "--allow-insecure-unlock" when I "init a node"? personal.unlockAccount(eth.accounts1) Any suggestion would be helpful. Thank ...
1
vote
0answers
7 views

How to get events on android with infura?

I am developing an app on Android, but Web3j does not support events on infura ( Should I use Infura with Web3j for Event filter? ) . What are the options, I did not find any alternative library?
1
vote
0answers
24 views

VM error: revert. revert The transaction has been reverted to the initial state. Note: The called function should be payable if

Hi Guys 👋 I have two contacts first one is SubToken and second one is MainContract. First I deploy MainContract after that I use createNewContract function and I create new SubToken. and then I ...
0
votes
1answer
19 views

Cannot Find Module Error for Truffle-contract

Error:- Uncaught Error: Cannot find module './truffle-contract.min.js' at c (web3.min.js:1) at c (web3.min.js:1) at index.html:27 <!DOCTYPE html> <html lang="en"> <head&...
0
votes
2answers
29 views

gas required exceeds allowance when deploying ERC721token

I am trying to deploy Smart-contract(ERC721) on my private ethereum network. But I have this issue. Here is my genesis. { "config": { "chainId": 3333, "homesteadBlock": 1, ...
0
votes
2answers
24 views

ParserError: Expected pragma, import directive or contract /interface/library definition

In an attempt to compile my ABI and verify my contract, I am getting the following warning: "ParserError: Expected pragma, import directive or contract /interface/library definition" on the first line ...
1
vote
1answer
17 views

Trouble accessing an array inside a struct inside a mapping via web3

Here are a few relevant code snippets from my smart contract struct Constituency{ uint16 id; string name; uint64[] cans; } mapping(uint => Constituency) public constituencies; ...
1
vote
0answers
17 views

Strange points of Casper algorithm

Currently, Ethereum developers are developing Casper Algorithm for Ethereum 2.0. According to their proposal, some validator are chosen randomly but validators has permanently authority to verify ...
2
votes
1answer
24 views

TypeError: Indexed expression has to be a type, mapping or array (is function (address) view external returns (string memory,string memory…)

I have 2 contracts first one is sub second one is main . First i deploy main and create a new subtoken. Then I want to access my maincontract in subToken contract but I cant :( When I compile this ...
0
votes
0answers
42 views

How to make password with mnemonic words?

i'm new on blockchain development and i'm trying to make a login like metamask in vuejs. Can someone teach me how to make 13 mnemonics word, where the last mnemonic is the password value get from an ...

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