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pragma solidity 0.4.8;
/*
* @title Learn Solidity: Function Modifiers in Solidity
* @author Toshendra Sharma
* @notice Example for the Learn Solidity
*/
// Let's talk about one of the most useful feature known as "function modifiers" in solidity
// Modifiers can be used to easily change the behaviour of functions,
// for example they can be used to to automatically check a condition prior to executing the function.
// They are inheritable properties of contracts and may be overridden by derived contracts.
// one example use case of function modifiers would be if we want to call the killContract function
// through only via owner/creator of the contract.
contract FunctionModifiers {
address public creator;
// Define consutruct here
function FunctionModifiers() {
// Initialize state variables here
creator = msg.sender;
}
//this is how we define the modifiers
modifier onlyCreator() {
// if a condition is not met then throw an exception
if (msg.sender != creator) throw;
// or else just continue executing the function
_;
}
// this is how we add a modifier to the function
// there can be zero of more number of modifiers
function kill() onlyCreator {
selfdestruct(creator);
}
}
