jirutka

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# The MIT License
#
# Copyright 2012-2014 Jakub Jirutka <jakub@jirutka.cz>.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
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chriseth

This gist shows how formal conditions of Solidity smart contracts can be automatically verified even in the presence of potential re-entrant calls from other contracts.

Solidity already supports formal verification of some contracts that do not make calls to other contracts. This of course excludes any contract that transfers Ether or tokens.

The Solidity contract below models a crude crowdfunding contract that can hold Ether and some person can withdraw Ether according to their shares. It is missing the actual access control, but the point that wants to be made

holiman

pragma solidity ^0.4.4;
contract X{
    
    string junk;
    function y() returns(string){
        //Uncomment the 'junk' below to make gas-measurements
        //junk="0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF012345

VictorTaelin

Make Ethereum massively scalable today with delayed computations

Suppose you're writing a contract which involves a huge amount of participants. As an example, think of an online, blockchain-based Trading-Card Game with tournaments. How would you program a playCard function? You might be thinking of something like this:

function playCard(uint player, uint card){
    ...
    else if (card == PROFESSOR_OAK){
        // shuffles the player's hand on his deck
 shuffleHand(player)

rfikki

admin.addPeer("enode://cd24a0c66055d788ce2bb77c2525915724a56de577b3e39c1a4dde347e60c83f082285a9d43a5ba0d7efc929699106d147e8d3612baafcaeb8f3075f36a82670@180.64.84.98:51044");
admin.addPeer("enode://86fb5f9e216c9fef5f97d3140d8d30ba13e2cc615ebb0b8e22975d296486e1f589baa6a2a4db6e0a1482f9b27a9e472efd94ec01cefc6e1d7e687dcdda0af5cc@46.105.118.30:30333");