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1500 questions
21
votes
3 answers

Can I set the gas price to whatever I want?

The default gas price is 0.02e12 Wei. But while creating transactions on the command line or Geth's Javascript console you can define your own gasPrice: web3.eth.sendTransaction({/* ... */, gasPrice: 123456789}); In Mist browser based Ethereum…
q9f
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20
votes
3 answers

How can DApp developers profit from their work?

Suppose that I make a new, cool DApp that gets very popular. In order to cover development costs and make some profit, I charge users of the app a small quantity which is required to use to app - all dealt by the contract, automatically. But, since…
MaiaVictor
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20
votes
7 answers

How to get ETH contract balance with Ethers.js

I am trying to get the ETH balance of a contract: const balance = await contract.getBalance(); but it fails: TypeError: contract.getBalance is not a function What I do wrong and how to fix the error?
porton
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20
votes
2 answers

Is transfer() still safe after the Istanbul update?

In other words, is using transfer() safe? function transfer(address contractB) public { contractB.transfer(1000); //balances[msg.sender] -= 1000; } How about using call.gas? function transfer2(address receiver) public { …
Robert Ggg
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20
votes
8 answers

Question on the terms 'distributed' and 'decentralised'

I am writing a paper on distributed ledger technologies, an umbrella term I have borrowed to put everything that has any relation to blockchains and distributed consensus. Under this umbrella term I am discussing primarily bitcoin, Ethereum,…
pn7a
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20
votes
1 answer

Are gas limit in transaction and block gas limit different?

What does gas limit mean? Are there two meanings of gas limit? gas limit in a transaction block gas limit
Satoshi Nakanishi
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20
votes
1 answer

What is the difference between transaction and message?

What is the definition of a transaction and a message in Ethereum? How are they different?
Satoshi Nakanishi
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20
votes
2 answers

Truffle vs Embark

Truffle Embark Can anyone explain the characteristics of, and differences between, the two frameworks?
BlockA
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20
votes
2 answers

Algebra symbology guidance for Ethereum Yellow Paper

There are numerate people who have limited experience in interpreting the algebra used in computer science papers. Therefore, it would be most useful if there were a list of all algebraic symbols used in the Yellow Paper, along with their definition…
Lee
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20
votes
5 answers

How to convert from Wei to Ether in React?

In React, I use a Web3js call function to get a value. The returned value is in Wei. However, I want to render it in Ethers. What would be the best way to do it?
Ruham
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20
votes
3 answers

Can you inherit from a contract already deployed to the blockchain?

So instead of doing something like: contract Parent { ... } contract Child is Parent { ... } Can the Parent be declared referencing an already deployed contract? contract Parent = 0x123123123... contract Child is Parent { ... }
Fernando Tiberti
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20
votes
4 answers

How to properly create a raw transaction and sign it using web3 in browser

I want to create and sign a transaction in browser using web3. In order to create a raw transaction, I think I have to do something like this (hopefully you can fill the gaps of my knowledge) var pk =…
S1r_Mar71n
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20
votes
3 answers

What are some examples of how inline assembly benefits smart contract development?

A lot of people have expressed excitement at the potential of using inline assembly in smart contracts. After seeing this comment on reddit I'm curious to see some basic (and more advanced, if you like) examples of how inline assembly may be used to…
Joël
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20
votes
4 answers

Should the constructor function be public?

In all the tutorials I'm watching nobody specifies public, but remix presents warnings that function visibility has not been specified, and public is assumed. Since I don't like warnings if possible, I am specifying public where necessary, but I…
urbanespaceman
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20
votes
2 answers

Getting ABI data for ERC20 tokens programatically with Web3

I am just starting to dive into Web3. I am trying to display the various ERC20 token values for a given Ethereum Address. The pieces I need to do this are: Token Contract Address Token Contract ABI Are there any programmatic ways to get the…
Shawn Tabrizi
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