Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with solidity
Search options not deleted
user 36566
Solidity is a contract-oriented, high-level language whose syntax is similar to that of JavaScript and it is designed for writing smart contracts in Ethereum to run on the EVM. Solidity is statically typed, supports inheritance, libraries and complex user-defined types among other features.
0
votes
1
answer
1k
views
How to use a variable with an Ether unit suffix
I have this code in my contract:
require(msg.value == 0.06 ether);
But I want to replace 0.06 with a variable.
So I tried this:
uint256 price = 0.06;
require(msg.value == price ether);
But this …
- 425
1
vote
1
answer
237
views
What type of decentralized programs require a Turing Complete programming language?
For example many Solidity (the Ethereum programming language) tutorials use a voting smart contract as an example to introduce smart contract programming basics. …
- 425
1
vote
1
answer
78
views
Can't wrap my head around a mapping of mappings
I'm trying to fully comprehend what is going on in a standard ERC721 token.
But this statement is really tripping me up:
// Mapping from owner to operator approvals
mapping (address => mapping (add …
- 425
4
votes
1
answer
1k
views
What is the difference between an approved address and an operator address?
I'm looking at OpenZeppelin's implementation of an ERC721 token and I'm lost at what the difference is between an approved address and an operator address.
Here's a code snippet:
/// @dev Checks ms …
- 425
2
votes
1
answer
188
views
How does Ethereum know who called a function first?
Scenerio 1
Say I have a function f().
Whoever calls the function first gets a reward.
Persons A, B, and C all call the function at roughly the same time.
Who will receive the reward?
Scenerio 2
…
- 425
2
votes
1
answer
381
views
What is the most efficient way to parse a string of integers to an array?
I perform an Oraclize query on an XML file, and receive this string in return:
["31", "25", "24"]
What would be the most efficient way to parse through this string and store the numbers into a uin …
- 425
8
votes
2
answers
11k
views
What's the point of ERC721Receiver.sol and ERC721Holder.sol in OpenZeppelin's implementation?
Relevant Code:
ERC721Receiver.sol
pragma solidity ^0.4.23;
/// @title ERC721 token receiver interface
/// @dev Interface for any contract that wants to support safeTransfers from ERC721 asset contracts … return
`bytes4(keccak256("onERC721Received(address,uint256,bytes)"))`
function onERC721Received(address _from, uint256 _tokenId, bytes _data) public returns(bytes4);
}
ERC721Holder.sol
pragma solidity …
- 425