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1500 questions
74
votes
9 answers
Help with very slow mist sync
I have seen other posts in reddit where users experienced slow sync times. I am using windows 10 and version 3.7 (I saw on gitter that other users on windows 10 had trouble with version 3.8 crashing).
My download speed is 4.19 MBS. I have adjusted…
Skier
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74
votes
5 answers
Why does uint8 cost more gas than uint256?
contract A {
uint8 a = 0;
}
costs 20150 + 2000 gas during creation.
as compared to
contract A {
uint a = 0; // or uint256
}
costing 5050 + 2000 gas during creation
It is odd that a variable that's taking less storage space is costing more…
uzyn
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74
votes
5 answers
What's the difference between proof of stake and proof of work?
The Ethereum frontier network currently uses a proof of work (PoW) consensus algorithm, while a future version of the network plans to utilise a proof of stake (PoS) algorithm instead. What's the difference between these two types of algorithm?
Jeff Coleman
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73
votes
3 answers
How do you refer to a contract own address inside it?
I am attempting to use 2 contracts together, and I need my 2nd contract to pass his own address to the first contract.
Is there an easy way to do this? Like this.address?
Or should I update my contract own address into a variable?
user697
- 2,176
- 3
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- 19
70
votes
3 answers
Why can't contracts make API calls?
The model that contracts can only accept and process data, instead of also being able to retrieve data from the Internet, seems limiting (even if not, it's less direct).
If a concern is that data or the Internet is unreliable, couldn't a contract be…
eth
- 85,679
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70
votes
5 answers
Get public key of any ethereum account
Can I somehow get the public key of an ethereum account knowing just the corresponding ethereum address (e.g. 0x54dbb737eac5007103e729e9ab7ce64a6850a310)?
Edward Ruchevits
- 1,285
- 2
- 15
- 24
69
votes
1 answer
Why is the average block time 17 seconds?
The network stats show a constant average blocktime of around 17 seconds. Whenever you check it is around 16~18 seconds.
Reading the blog post by vitalik buterin it states the block time should be 12 seconds on average. (Update: Ok, more recent…
q9f
- 32,913
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69
votes
7 answers
How can you decompile a smart contract?
On the blockchain I can inspect the code of a contract, and see the EVM opcodes. Is there a way to decompile this and convert it back to (Solidity) source code?
J-B
- 8,941
- 16
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68
votes
5 answers
What is the cost to store 1KB, 10KB, 100KB worth of data into the ethereum blockchain?
Whatever is stored in the blockchain is immutable which means I can fetch this data back in the future. As of today (2016-feb),
How does one store a 1kb, 10kb, or 100kb or arbitary data/text in the ethereum blockchain? What is the code needed to do…
Patoshi パトシ
- 4,800
- 7
- 45
- 93
68
votes
6 answers
What number of confirmations is considered secure in Ethereum?
In Bitcoin, 6 confirmations are considered secure (very low probability of transaction/block reversal).
What is the current number in Ethereum?
eth
- 85,679
- 53
- 285
- 406
68
votes
5 answers
Why are selfdestructs used in contract programming?
I'm reading bits and pieces that selfdestructs within contracts are a good thing. Can someone explain what the benefits are of doing a contract selfdestruct when it comes to Ethereum programming? Is there a difference if you're using different…
high110
- 4,756
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68
votes
4 answers
What OPCODES are available for the Ethereum EVM?
The Ethereum virtual machine has a large number of operation codes and base level instruction sets. Is a complete listing available?
Ethan Wilding
- 4,821
- 7
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- 31
67
votes
9 answers
How to delete an element at a certain index in an array?
Anyone know how to delete an element in a array? Is there any built in method to do that?
If not, does anyone know of how to implement such a method?
user697
- 2,176
- 3
- 15
- 19
66
votes
14 answers
Hardhat - How to interact with a deployed contract?
I can deploy a contract using ethers and Hardhat with the following:
const myContract = await hre.ethers.getContractFactory("SomeContract");
const deployedContract = await myContract.deploy();
I can even interact with the methods from that deployed…
JohnWLIV
- 763
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66
votes
2 answers
What is the relationship between Mist and Ethereum Wallet?
In https://github.com/ethereum/mist/releases 0.3.6 the files are named Mist. Starting in 0.3.7 the files are named Ethereum-Wallet.
Will files named Mist take over in the future, or will there be 2 separate files Mist and Ethereum-Wallet?
eth
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