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1500 questions
36
votes
10 answers
How can you handle an expected throw in a contract test using truffle and ethereum-testRPC?
Is it possible to write a test using truffle that attempts to confirm that a throw occurs in a contract? For example, if I had a contract with function...
contract TestContract {
function testThrow() {
throw;
}
}
if I write a test in…
thedob
- 615
- 1
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- 7
36
votes
8 answers
Insufficient funds for gas * price + value
Sending Address has over 1 Eth in current Balance.
Using the Geth console, I can send many transactions of any amount less than .033
eth.sendTransaction({to:'0x8B9da75fda99bAd680154050Ba386523CA3AD112',…
John Heeter
- 521
- 1
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- 5
36
votes
9 answers
How to get transactions by account using web3 js?
I'm sure this question was asked before, but I did not find any result that helped my problem.
How can I get the transactions (in and out) for a given account? I use nodejs and web3?
With this line I get the number of sent…
Christoph Bergmann
- 601
- 1
- 5
- 6
36
votes
3 answers
How to explore all transactions for a given account?
After beeing able to check account balances, I am looking for a method to list all transactions for a given Ethereum account through json-rpc protocol. I haven't found any method suitable for that on https://github.com/ethereum/wiki/wiki/JSON-RPC .…
Juan Ignacio Pérez Sacristán
- 3,550
- 9
- 43
- 73
36
votes
1 answer
What is the receive keyword in solidity?
Solidity has a receive keyword. What is it and how do I use it?
Shane Fontaine
- 18,036
- 20
- 54
- 82
36
votes
6 answers
How to find the date of an Ethereum transaction while parsing it with web3?
Is there a way to know the date of a transaction by looking at the raw blockchain data?
I know that Etherscan and other blockchain explorers have dates for the transactions, but I couldn't find a way to do it via web3.
web3.eth.getTransaction, and…
user3498
- 735
- 2
- 9
- 12
36
votes
3 answers
'internal' keyword in a function definition in Solidity
Does the internal keyword in a function definition such as:
function doSomeThing(uint _param) internal {...}
work similar to designating a method as private in other languages and thus makes the function only callable from within the contract?
Terek Judi
- 525
- 1
- 4
- 7
36
votes
6 answers
What caused this error: Attempting to run transaction which calls a contract function, but recipient address is not a contract address
I have a contract and a set of mocha tests. I recently switched from using the ethereum client that comes with truffle (the one you get when you run truffle develop) to the ganache-cli. Somehow, in switching back and forth between them, I caused my…
Alex Altair
- 883
- 1
- 7
- 13
36
votes
2 answers
Can you create a constant (read-only) state variable in Solidity?
Can you declare a constant variable in Solidity?
const uint answer = 42;
Or is the only way to do it with a const function?
function GetAnswer() constant returns(uint ret) {
return 42;
}
I know you could always create a normal public variable…
Raine Revere
- 3,600
- 2
- 23
- 34
36
votes
3 answers
What is a replay attack?
During the launch of the frontier network, users were cautioned not to reuse keys from the Olympic testnet in order to prevent "replay attacks". What is a replay attack, and why would re-using a key from the testnet make someone vulnerable to one?
Jeff Coleman
- 22,059
- 17
- 77
- 91
36
votes
6 answers
Can I download the whole blockchain from somewhere?
Bitcoin used to offer sharing/downloading a bootstrap.dat which contains the whole blockchain.
Are there alternatives to getting it trickling through the peer-to-peer network? Can I just download it somewhere? Wouldn't this be ideal for distribution…
Donavan Theodor
- 1,943
- 3
- 20
- 28
36
votes
2 answers
Ethereum ecrecover signature verification and encryption
The question of signing and verifying signatures with Solidity has been asked in these questions, both of which I have tried to study:
How can I sign a piece of data with the private key of an Ethereum address?
How can I verify a cryptographic…
arik
- 503
- 1
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- 5
36
votes
5 answers
How to access the event log by knowing the contract address (web3)?
How can I access a log stored in one of the tx of the contract via web3?
Code example:
event newtest(string indexed name, uint indexed idlevel,string indexed multib, string objmulti, uint objnm);
and
newtest('test',5,'testj','obj2',30);
Let's say…
b1818762
- 363
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- 5
36
votes
6 answers
Can't send transaction -- "Exceeds block gas limit" or "Intrinsic gas too low"
I'm trying to send Ether using geth 1.3.5, like this:
eth.sendTransaction({
from: eth.accounts[0],
to:'0x[ADDRESS_HERE]',
value: web3.toWei(5, "ether"),
gas:21000
});`
And I'm getting "Exceeds block gas limit"
When I try:
with gas=5000 I…
Dan Sandberg
- 463
- 1
- 4
- 5
36
votes
3 answers
ERC20 vs ERC223. List of differences
Is there a list of improvements that we will have in ERC223?
Are there examples of contracts?
Is there a migration path for existing ERC20 tokens?
rstormsf
- 4,337
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- 25
- 42