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Not able to successfully send Transactions via MetaMask on Firefox Browser

Does anybody help me figuring out why I am getting failed transaction here?What does this error means? Few days back,with the same line of code,I was able to successfully send transactions. An update:...
-1
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0answers
8 views

After Creation Contcact and receive ETH it answer messagem ERRO and Block Owner

After Creation Contcact and receive ETH it answer messagem ERRO and Block Owner It was made with CODE Pattern when Eth was watched like Model to ERC 20 How to cancel or erase contract and Get Back ...
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1answer
21 views

Error Handling on Contract Calls to Other Contracts

I'm trying to call a function from another contract and need a way to accommodate errors. Say contract A has the method getBalance: function getBalance(address x) public view returns(uint ...
-1
votes
1answer
35 views

How many projects are there which implement ERC1155 standard?

New ERC1155 standard which is thought to be an improved version of ERC721 and ERC20. But I see many projects still prefer ERC20 or ERC721 standards. If so, do you know any projects implementing ...
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1answer
11 views

How does Ethereum's Makerdao Dai stablecoin differ from EOS's Equilibrium EOSDT stable coin?

What are the main differences from Ethereum's makerdao dai stablecoin to EOS's equilibrium EOSDT stablecoin? And are there other stablecoins like these two that are decentralized and issued via a ...
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1answer
14 views

Kovan contract creation gas limit behavior

I have a fairly large contract that I must create on Kovan network for testing. There is fairly weird behavior occurring when I am trying to create the said contract. Behavior being: whenever ...
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0answers
15 views

Comparison of 2 child-contract-values in factory-contract

in my solidity code I create a tracking-contract and auction-contracts out of a factory-contract. The last function 'a4_Payment' of the auction-contract should be triggered out of the master-contract ...
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0answers
9 views

How to deploy smart contract with private wallet?

I am now deploying smart contract using ganache localhost:7545, i want to use infura ropsten account to deploy. Most examples uses Metamask, but i want use own ethreum wallet. How can i use to deploy? ...
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1answer
29 views

Invalid sender address, failed to deploy a transaction to the blockchain network

Description I'm trying to deploy a contract to rinkeby network, but everytime I like to deploy the contract it throwing error as invalid sender. Compile code const path = require('path'); const fs =...
1
vote
1answer
27 views

Different gas usage of trivial reverting contract function

We are currently testing functions on Ropsten test network and have an issue regarding the gas usage. Our functions sometimes use 12 gas more and we can not fathom why that would be the case. To test ...
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2answers
28 views

invalid number value for power of 18

Using web3js v1.2.1 const contract = new web3.eth.Contract(abi, '0x29...'); const amount = 1 * 10 ** 18; const data = contract.methods.transfer(recipient, amount).encodeABI(); I get error : invalid ...
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2answers
28 views

Error: Invalid JSON RPC response: “” from web3

I run: geth --rinkeby --rpc --rpcport=8545 --rpcaddr=192.168.1.37 It works in console: geth attach http://192.168.1.37:8545 > eth.syncing false > eth.accounts ["...
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votes
1answer
15 views

mistake about importing another contract into one contract in remix

I import another contract Hello.sol in contract test1.sol, but after deploying it, only contract Hello's function is displayed in the run interface, not contract test1's function???What is wrong?What ...
1
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0answers
6 views

Offchain voting

Are there any voting based approaches where voting would happen off chain, via signed messages, but then the result could be indepedently verified or even stored on chain? Voting rights are based on ...
0
votes
1answer
10 views

What’s the 0x4 precompile?

Simple question but I couldn’t find the answer. Is it the datacopy precompile? and if yes, what it does?
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1answer
25 views

CompilerError: Stack too deep, try removing local variables [on hold]

interface AgreementInterface { function newAgreement(string _leaser, bytes32 _houseId, string _houseAddress, string _describe, bytes32 _signInfo, uint256 _rental, uint ...
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votes
1answer
18 views

Not able to generate java wrapper class from solidity smart contract using truffle

I'm trying to generate java wrapper class of solidity smart contract using truffle but not getting wrapperclass.java file Here is an command which i've used to generate abi/Json of that contract ...
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0answers
13 views

Trying to send ERC20 token with Javascript button without success

I am trying to send an ERC20 token with the following code via web3.js. It was working until a week ago and then it stopped. Am I doing something wrong? Upon clicking it no longer interacts with ...
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0answers
9 views

Is there any example of a drizzle-react dapp implementation that uses render props?

Render props were added after React 16.3 and the github readme for drizzle-react suggests to use them. The problem for is that there is no updated documentation (other then the small example in the ...
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0answers
19 views

getPastEvents undefined(please help)

I had asked this question before. I looked carefully at the exchange section, which I advised, and I think there is no problem with the exchange section. At least in my opinion there is no problem and ...
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0answers
27 views

solidity - Send token without using transfer function [on hold]

function purchaseWithToken(uint256 amount) public { require(amount > 0 , "Purchase require amount > 0"); require(_balances[msg.sender] >= amount , "amount not enough"); _balances[...
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1answer
17 views

How a consensus algorithm is implemented in a private Blockchain network ( ethereum )? [on hold]

How to implement a new custom consensus algorithm in a network.
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0answers
9 views

How Proof-Of-Learning can be implemented?

Seen a paper on Proof-Of-Learning and wanted to know-how the consensus works and how to implement it in ethereum?
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1answer
12 views

Can block validation be done using machine Learning Algorithms?

I am looking for a new era of products that leverages the potential of Machine Learning and the blockchain, Thinking of different aspects of Blockchain which can be improved with the help of machine ...
0
votes
1answer
20 views

How can a smart contract payable based function returns value against any purchase

I am trying to get a return value from the payable function, the idea is a user must pay the fees and in return, he will get his special code. My JS test code is as follow it('get special code ...
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votes
1answer
9 views

How to set constructor parameters before deploying in remix?

I don’t understand how it works. I created a contract with a constructor with parameters. But I don’t understand where to pass these parameters to the constructor. Or I need to set params after ...
0
votes
1answer
10 views

How to have ecrecover return nothing ? I means which value for malformed input?

I have a contract where the hash value is also the key to unlock the money. As the full ecrecover parameters are fetched from transaction parameters, and it was compiled in 2016, it is vulnerable to ...
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votes
1answer
21 views

How can I interaction to a contract by address from another contract?

I have to access methods of one contract from another contract body. How can I realize that using just a address of first contract? contract KittyShelter{ address KittenRegistry; //Here, ...
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2answers
17 views

Create fastest possible localhost Ethereum test net

Is there an Ethereum test blockchain (similar to Ganache) which prioritises calculating transactions and creating a local blockchain 'db' as quickly as possible? Requirements: - Calculate ...
1
vote
1answer
23 views

Is there any way to extract transactions in uncles?

As stated in the wiki: Note: An uncle doesn't contain individual transactions. I would still like to extract transactions from uncle blocks. Is there any method available for doing so?
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0answers
16 views

Can a factory-contract access/read/modify variables in generated child-contracts?

at the moment I am experimenting with the factory/child-logic in solidity. With my factory contract I am able to create child contracts in which an auction is executed. Now I want to return a variable ...
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0answers
18 views

PIVX fork CryptoDezire Coin SendRawTransaction not working

A CDZC coin basically fork of PIVX . I am trying to send coin via rpc calls. Successfuly created RawTxn, SignRawTxn but unable to SendRawTxn. `await rpc.listunspent().then(async r => { ...
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0answers
6 views

How to save as g6 using graphs.nauty_geng in Sage? [on hold]

I am trying to get Sage to generate all graphs with 7. I typed in the following: g7=[g for g in graphs.nauty_geng('7') ] I’d like to save as g6 data typeI file. How to do ? I want to use the g6 ...
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0answers
15 views

Is it normal that the last transactions don’t appear on Etherscan? [on hold]

Last block with latest transaction was mined 4 hours ago. Of course, other explorers can see the latest ones but I need the Etherscan feature of accessing the details storage change of transactions. ...
1
vote
1answer
19 views

Creating a contract instance

Is it generally better to define a contract instance once, then pass it through your components like... class Parent extends React.Component{ constructor(props){ super(props); ...
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0answers
23 views

Function Call when Sender Must Be Certain Address

I have a contract on Ropsten, and when I do this is python, I get a result: result = contract.functions.getLastUpdateTime(0).call() So I know the abi is there, the address, etc. There's another ...
1
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0answers
7 views

How to tell if `geth` connected to EVM One?

I'm using the EVM One back-end with ewasm/geth according to the following instructions. Geth seems to be starting up as usual with the following command: geth --vm.evm=./libevmone.dylib How can I ...
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2answers
17 views

How to set a transaction timeout in txpool properly?

I want to limit transaction pending time to 5 seconds, after that the transaction considered as failed; does --txpool.lifetime solve the problem ?
0
votes
1answer
15 views

TypeError: market.FileViewed is not a function while trying to watch event

I want to watch for fileViewed event and it throws TypeError: market.FileViewed is not a function in marketplace.FileViewed{ ^ My solidity contract: pragma solidity ^0.5.0; contract ...
0
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0answers
14 views

cloning div container number of deployed child contracts time and put their data inside div container

Sorry for the silly question. I have a div container "product-card" , I want to loop the number of my deployed smart contracts time. every time when I loop I want to clone this div container and ...
0
votes
1answer
15 views

Giving a big nonce in transaction doesn't return anything?

When we put a low nonce in transaction options we got "nonce too low", but when a put a big nonce (bigger then transaction count) we got anything why ?
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0answers
8 views

How can I change the text message on connection request window of metamask?

I want to change the message in connection request window using web3js. I have attached screenshot here. kindly check it.
0
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0answers
6 views

hwo to identifie error from transaction error object?

is it possible to know what is the reason of transaction error from "error" object (nonce, insufficient fund ..) is there status or something to test using it ? Geth error message is generic, I ...
0
votes
1answer
12 views

How do Miner choose transactions for a block?

i am wondering how a Miner chooses the transactions, he want to mine inside a block. For example, a Miner has got the Transactions T1 and T2 at the moment he starts a new mining work. This Miner is ...
0
votes
1answer
10 views

Quorum permissioned network

How can I permission a quorum network? Imagine I have 3 nodes in my network and I install another node in my friends house. How can I prevent my friend add more nodes to my quorum network? thanks
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2answers
27 views

solidity - How to detect an ERC token has just transferred money to my contract

I am developing an application that automatically converts eth, usdt ... to my token when they transfer money to my contract address. With eth, I can do it, but how to detect other erc tokens, ...
0
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0answers
19 views

Parity Aura - Error: Transaction has been reverted by the EVM

I run the following code against two private blockchains, parity-aura and geth-clique. Why does the parity transaction revert and why does it use 6,000,000gas when it should actually only use about ...
0
votes
1answer
6 views

truffle compile/migrate gives error: “ParserError: Expected pragma, import directive or contract/interface/library definition.”

The tutorial I'm following created a 2_Migrations.sol with the following: const Token = artifacts.require("Token"); module exports = function(deployer) { deployer deploy(Token); }; "Truffle ...
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votes
1answer
20 views

Could I implement a kill switch in my solidity program?

I was wondering if there was a way to put a killswitch into my solidity code? I am using v0.4.21+commit.dfe3193c Thanks a bunch!
0
votes
1answer
8 views

How estimate GAS from a contract call with Web3j

I'm trying to estimate gas cost of a contract call, i need to send a string to a contract, but i need to see if i overtook the GAS limit. I'm trying like this: Transaction t = Transaction....

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