Dappsys

Safe, simple, flexible building-blocks for smart-contract systems.


Auth
ds-auth ds-guard ds-roles
Token
ds-token ds-vault
Oracle
ds-cache ds-value
Util
ds-exec ds-math ds-note ds-proxy ds-stop ds-thing
Gov
ds-multisig

DSExec

Better exception handling

Base contract which wraps .call with internals .exec and .tryExec, which handle exceptions more naturally.

  // exec.sol - base contract used by anything that wants to do "untyped" calls

// Copyright (C) 2017  DappHub, LLC

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.13;

contract DSExec {
    function tryExec( address target, bytes calldata, uint value)
             internal
             returns (bool call_ret)
    {
        return target.call.value(value)(calldata);
    }
    function exec( address target, bytes calldata, uint value)
             internal
    {
        if(!tryExec(target, calldata, value)) {
            revert();
        }
    }

    // Convenience aliases
    function exec( address t, bytes c )
        internal
    {
        exec(t, c, 0);
    }
    function exec( address t, uint256 v )
        internal
    {
        bytes memory c; exec(t, c, v);
    }
    function tryExec( address t, bytes c )
        internal
        returns (bool)
    {
        return tryExec(t, c, 0);
    }
    function tryExec( address t, uint256 v )
        internal
        returns (bool)
    {
        bytes memory c; return tryExec(t, c, v);
    }
}

Tools for dapps

We believe that the free software movement is the most important cultural predecessor to the modern-day renaissance in decentralized technologies.

To catalyze the growth of this ecosystem, and to empower hackers to participate, we’re building a comprehensive suite of blockchain-oriented developer tools in the spirit of the Unix philosophy.

Dapp is all you need to start developing for Ethereum. It creates new dapps, runs Solidity unit tests, debugs, deploys, launches testnets, and more.

Seth is a handy tool for slicing and dicing transactions, querying the blockchain, converting between data formats, performing remote calls, and other everyday tasks.

Hevm is our own EVM implementation with a nimble terminal-based Solidity debugger. It’s used for dapp test and dapp debug.

Evmdis is an EVM disassembler written and maintained by Nick Johnson. It’s useful to make sense of EVM bytecode, especially when developing contracts at the assembly or raw bytecode level.

Dappsys - smart contract building blocks

We also maintain Dappsys, an audited collection of smart contract building blocks designed to complement each other. They include;

Using these proven parts lets us focus on the novel features of the systems we develop. We share Dappsys to benefit the smart contract ecosystem.