CryptoCoinsInfoClub.com

Ethereum Browser Solidity

Remix - The Ethereum Wiki

Remix - The Ethereum Wiki

Remix, previously known as Browser Solidity, is a web browser based IDE that allows you to write Solidity smart contracts, then deploy and run the smart contract. You can run Remix from your web browser by navigating to , or by installing and running in on your local computer. Instead of running Remix from , you can download the latest package from . You will have to switch to the branch gh-pages. Download the .zip file with a name similar to remix-0f851e3.zip into a directory on your computer. Unzip the .zip file. Load index.html in your browser. The advantage of running Remix from your local computer is that it can communicate with an Ethereum node client running on your local machine via the Ethereum JSON-RPC API . You can then execute your smart contracts in Remix while connected to your local development blockchain, the Testnet blockchain, or the Mainnet blockchain. Whether you are running Remix from it's website, or from your local installation, you should see a screen resembling the one below. Following is the source code for a simple example that you can copy and paste into the left section of your Remix screen. 1 pragma solidity ^0.4.8; 2 3 contract Hello { 4 5 // A string variable 6 string public greeting; 7 8 // Events that gets logged on the blockchain 9 event GreetingChanged(string _greeting);10 11 // The function with the same name as the class is a constructor12 function Hello(string _greeting) {13 greeting = _greeting;14 }15 16 // Change the greeting message17 function setGreeting(string _greeting) {18 greeting = _greeting;19 20 // Log an event that the greeting message has been updated21 GreetingChanged(_greeting);22 }23 24 // Get the greeting message25 function greet() constant returns (string _greeting) {26 greeting = _greeting;27 }28 } On the right Continue reading >>

Deploy To Ethereum Network (from Browser-solidity)

Deploy To Ethereum Network (from Browser-solidity)

0x037c897d77109a0d99186e7456ca7f52f2deae9f Unlike when deploying to local JavaScriptVM, it takes a while for the above state change (state registered in block). If there is no change on the screen all the time in this state, there is a possibility that registration has failed. (When checking with the browser's DevelopmentMode, it often occurs that JavaScript has caused an error.) BrowserSolidity is still under development and depending on the Version the Create operation may fail. In that case, please adjust the version of BrowserSolidity or try to deploy directly from the command line shown in the following section. Set "HelloWorld" in the same way as when running in local JavaScriptVM. Enter "Hello World" and press 'setGreeting'. Wait for the transaction to be issued and enter the block. A transaction is created and the results are displayed. If you press 'getGreeting', the value of the field will be retrieved. Since this process is contant, it does not involve issuing transactions, so the results are displayed immediately. Deployed contracts are instantiated on the BlockChain, so you can specify addresses to retrieve them. Press 'AtAddress' and the address of the contract you created in the dialog 0x037c897d77109a0d99186e7456ca7f52f2deae9f You can load deployed contracts as described below. Continue reading >>

Compile And Deploy Solidity Contract

Compile And Deploy Solidity Contract

Facebook Google Linkedin Twitter Telegram Contracts live on the blockchain in an Ethereum-specific binary format (Ethereum Virtual Machine (=EVM) bytecode). This tutorial explains how to deploy the byte code to Ethereum Blockchain For the frontier release, geth supports solidity compilation through system call to solc, the command line solidity compiler by Christian R. and Lefteris K. Easy wayIts very easy to install solc using npm the package manager for NodeJS the command is npm install solc Easier way Browser-SolidityIf you just want to try Solidity for small contracts, you can try browser-solidity which does not need any installation. If you want to use it without connection to the Internet, you can also just save the page locally or clone Building from SourceAssuming you are using Ubuntu 14.04 sudo apt-add-repository ppa:george-edison55/cmake-3.xsudo apt-get -y updatesudo apt-get -y install language-pack-en-basesudo dpkg-reconfigure localessudo apt-get -y install software-properties-commonsudo add-apt-repository -y ppa:ethereum/ethereumsudo add-apt-repository -y ppa:ethereum/ethereum-devsudo apt-get -y updatesudo apt-get -y upgrade git clone --recursive webthree-umbrella./webthree-helpers/scripts/ethupdate.sh --no-push --simple-pull --project solidity # update Solidity repo./webthree-helpers/scripts/ethbuild.sh --no-git --project solidity --all --cores 4 -DEVMJIT=0 To ensure solc is installed and ready to use, you can verify it by running eth.getCompilers() in geth consoleIf you have it installed, it should output something like this: source = "contract test { function multiply(uint a) returns(uint d) { return a * 7; } }" This contract offers a unary method: called with a positive integer a, it returns a * 7.You are ready to compile solidity code in the geth JS co Continue reading >>

Blockwatch: Tools For Working Withsolidity

Blockwatch: Tools For Working Withsolidity

I explain cool tech to the World. I am a Technical Writer and blogger. I have crazy projects in progress and will speak to anyone who listens. Blockwatch: Tools for Working WithSolidity Recently a group of Blockchain enthusiasts at the co-working space I occasionally work from decided that it was time we stopped talking about Blockchain and actually learned how to create something based on it. We wanted to create a coin or token for the community to use internally, and whilst the project has stalled for now, I started investigating Ethereum in more depth, and the language it uses for creating smart contracts, Solidity . I will cover the language itself in more detail in the future (when I understand it more myself!), but in this post, I will cover some of the tools available for working with the language. Your starting point is the official Ethereum clients , available for all operating systems and in Go , C++ , Rust , and Python . All support the full breadth of classes and methods for Solidity and many of the other tools listed here will need them as dependencies. There is an unofficial client for JavaScript . The repository I linked to is out of date, but it contains a useful reference to where to now find the libraries you need. Mix promised to be a fully-fledged Solidity IDE, but it never materialized and Remix is its the web-based alternative. You can lint, compile, debug, run, and analyze your Solidity code based on different versions of the Ethereum compiler. You can also run your own local copy of Remix in the browser, or as a browser extension. The official Ethereum wallet and mist applications allow you to deploy contracts to networks, but not much else, so you should make sure your code is finished before using them. If you use any of the IDEs based on the Continue reading >>

Learning Solidity Part 1: Contract Dev With Metamask

Learning Solidity Part 1: Contract Dev With Metamask

Learning Solidity Part 1: Contract Dev with MetaMask Loving Ethereum, Casper, Cryptoeconomics, blockchain, open source, and of course Meditation 1. The Chrome web browser - Download here 2. The Metamask Chrome extension - Download here Metamask allows you to sign Ethereum transactions without running a full Geth node. ETH is the main currency on the Ethereum network. However, Ethereum can support multiple currencies and ETH eventually will not have privileged status. Executing transactions on Ethereum either runs computations or stores data. This Costs the network CPU cycles or storage space. That cost is paid for by the account that initiates the transaction. The payment is called "gas". Gas is currently paid using ETH. At the time of writing this, 1 GAS = 0.00001 ETH. Morden is a name for one of the most popular public Ethereum TestNets. It is the same as the Ethereum network, but ETH on Morden is worth nothing. You can get ETH for free on Morden from many Morden "ETH faucets". To easily deploy contracts to Morden, we will need Metamask. First install Metamask if you haven't already here . In the top right corner of Chrome you should now see the cute Metamask fox :) Click on the icon and let's start creating your Ethereum wallet! Agree to the terms of service. At the time of writing this, Metamask is beta software, so if you want to use it for the MainNet, just don't store or transact more than you can lose. Now click CREATE NEW VAULT. This will begin the wallet generation process. Note: If you want to use this account for anything of value, use a unique randomly generated password stored in a password manager like 1Password or LastPass . Back up your randomly generated "seed phrase". This is your master password for the vault. Keep it extremely secure, and definitel Continue reading >>

Ethereum/remix - Gitter

Ethereum/remix - Gitter

Ethereum IDE and tools for the web (node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit. app.js:62:15091console.trace(): app.js:62 [537]Continue reading >>

How To Write Your First Smart Contract In Solidity

How To Write Your First Smart Contract In Solidity

How to write your first smart contract in solidity The problem with learning to code on ethereum smart contracts is to know where to start from. After just learning about blockchains and ethereum, you try to google, in the hopes of getting started but you are stymied looking at dozen possible options with complicated stuff you dont understand. You wanted to make a Dapp that would eventually go on a blockchain, but cant even begin to begin. Well, there is a good news. Creating a smart contract doesnt have to be that daunting. With just a basic understanding of any object oriented language (C++, C, java, etc), the right tools and set-up at your disposal, you could easily create simple to complex smart contracts and test them out in little to no time- without needing to get into the pain of knowing how to deploy the contracts (though you will eventually need to know about the Dapp frameworks and tools) Follow this link ( ) to browser-solidity to kickstart your journey to coding smart contracts. All the codes will be written in solidity in this tutorial. Browser-solidity is mostly used for debugging code but it is more than enough to get a start. We assume you have basic understanding of blockchains and how they work. In this demonstration :- You will learn how to use browser-solidity. And how to write a simple token sale contract and call its methods. When were done youll know exactly how to write some deep looking smart contract code, ready to dive into the complicated task of actually deploying the contract to a live blockchain. After you click on the browser solidity link (make sure you use that link), you will find a default smart contract named ballot.sol (dont worry if you dont) in an interface as shown below. The panel on the right has a few options that you should Continue reading >>

Solidity Realtime Compiler And Runtime

Solidity Realtime Compiler And Runtime

Publish all open files to an anonymous github gist. Copy all files to another instance of browser-solidity. You can also load a gist by adding the following #gist=GIST_ID to your url, where GIST_ID is the id of the gist to load. Execution environment does not connect to any node, everything is local and in memory only. Execution environment has been provided by Mist or similar provider. Execution environment connects to node at localhost (or via IPC if available), transactions will be sent to the network and can cause loss of money or worse! If this page is served via https and you access your node via http, it might not work. In this case, try cloning the repository and serving it via http. This tab provides support for formal verification of Solidity contracts. This feature is still in development and thus also not yet well documented, but you can find some information here . The compiler generates input to be verified (or report errors). Please paste the text below into to actually perform the verification. We plan to support direct integration in the future. Continue reading >>

Build Your First Ethereum Smart Contract With Soliditytutorial

Build Your First Ethereum Smart Contract With Soliditytutorial

Finance & Tech Nerd, Investor, Blockchain & Crypto Enthusiast, Wannabe Polymath, Master of Discipline in Training, Laissez Faire. Talk Is Cheap. Build Your First Ethereum Smart Contract with Solidity Tutorial So you wanna build a smart contract? Perhaps you want to understand how they work, maybe you want to build your own Dapp, maybe you want to launch the very first billion dollar ICO (sarcasm)... Regardless of your intentions, learning how smart contracts work is invaluable. The Ethereum platform possesses enormous potential to create Dapps that could change the way we interact on the web in the decades to come. While Ethereum deploys smart contracts that work much like a standard blockchain transaction, they yield a conditional statement that must be met before a function(s) is executed. Smart contracts can be used for voting, crowdfunding, blind auctions, multi-signature wallets and MUCH more. Bob has his own scrap metal depot business in the United States, Eric is his iron scrap supplier. Eric is based out of China. Bob and Eric have a GREAT business relationship. They trust each other and have been doing business for a long time. Both have booming businesses, and Bob in particular sells out of iron scrap on a routine basis. Bob deploys a contract where once his iron scrap inventory reaches a certain range, he automatically sends an order out to Eric for X lbs of iron scrap at Y ether per ton. Eric agrees to the arrangement and accepts Bobs payment in ether right away. Eric gets to work right away and starts fulfilling Bobs order. Eric can exchange his ether at a local exchange online for Yuan for a tiny fee and itll be processed instantaneously. Whether Eric decides to hold ether or convert to Yuan is his choice, but either way he can now put this capital to wor Continue reading >>

Installing The Solidity Compiler

Installing The Solidity Compiler

We provide up to date docker builds for the compiler. The stablerepository contains released versions while the nightlyrepository contains potentially unstable changes in the develop branch. docker run ethereum/solc:stable solc --version Currently, the docker image only contains the compiler executable,so you have to do some additional work to link in the source andoutput directories. Binary packages of Solidity are available at solidity/releases . We also have PPAs for Ubuntu. For the latest stable version. sudo add-apt-repository ppa:ethereum/ethereumsudo apt-get updatesudo apt-get install solc If you want to use the cutting edge developer version: sudo add-apt-repository ppa:ethereum/ethereumsudo add-apt-repository ppa:ethereum/ethereum-devsudo apt-get updatesudo apt-get install solc We are also releasing a snap package , which is installable in all the supported Linux distros . To install the latest stable version of solc: Or if you want to help testing the unstable solc with the most recent changes from the development branch: Arch Linux also has packages, albeit limited to the latest development version: Homebrew is missing pre-built bottles at the time of writing,following a Jenkins to TravisCI migration, but Homebrewshould still work just fine as a means to build-from-source.We will re-add the pre-built bottles soon. brew updatebrew upgradebrew tap ethereum/ethereumbrew install soliditybrew linkapps solidity If you need a specific version of Solidity you can install aHomebrew formula directly from Github. Follow the history links until you have a raw file link of aspecific commit of solidity.rb. brew unlink solidity# Install 0.4.8brew install Gentoo Linux also provides a solidity package that can be installed using emerge: If you are interested what CMake optio Continue reading >>

Etherum Browser-solidity

Etherum Browser-solidity

Etherum Browser-Solidity More than 1 year has passed since last update. EthereumSmart Contract Browser-Solidity Remix+(New File) pragma solidity ^0.4.0;contract test { int a; function set_num(int num){ a = num; } function get_num() returns(int){ return a; }} rpc~JSON-RPC --unlockgeth > geth --networkid 12345 --datadir ABC --nodiscover --rpc --rpccorsdomain "*" --rpcport 8545 --rpcaddr "localhost" --rpcapi "web3,eth,net,personal" --unlock console 2>> ABC/geth.log Web3 ProviderWeb3 Provider Endpoint:geth localhost--rpcaddr "localhost"localhost 382blockNumber: 382 > eth.getTranction("0x29816e23fb48ae82be4ebe7f1546961c4f27e02f4ab8f5440e40003960685f79"){ blockHash: "0x7a29cfb1d3e37b5b888025678557da08b21424fed68a3b0c6ccacf533389da7f", blockNumber: 382, from: "0x08ade1b1470fa937908c0ff605d0028a2a25d2e5", gas: 2957117972, gasPrice: 20000000000, hash: "0x29816e23fb48ae82be4ebe7f1546961c4f27e02f4ab8f5440e40003960685f79", input: "0x6060604052341561000c57fe5b5b60c68061001b6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff1680633e27a8e8146044578063545a48d0146067575bfe5b3415604b57fe5b60516084565b6040518082815260200191505060405180910390f35b3415606e57fe5b60826004808035906020019091905050608f565b005b600060005490505b90565b806000819055505b505600a165627a7a72305820bd7eca5b9bbc049ce826fbe5aa22e94cbda268abf1675332bbf3849a465848610029", nonce: 8, to: null, transactionIndex: 0, value: 0} Remixinterface2 > var abi = [{"constant":false,"inputs":[],"name":"get_num","outputs":[{"name":"","type":"int256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"num","type":"int256"}],"name":"set_num","outputs":[],"payable":false,"type":"function"}]undefined> abi[{ constant: false, inputs: [], name: "get_num", outputs: [{ name: "", Continue reading >>

Smartcontractbrowser-solidity

Smartcontractbrowser-solidity

SmartcontractBrowser-solidity More than 1 year has passed since last update. EthereumGoGethSmartContractSoliditySmartContract SmartContractIDEDapps geth --networkid "11" --datadir "path_to_directory" --genesis "path_to_genesisjson" --unlock "your_account_password" --rpc --rpcaddr "localhost" --rpcport "8545" --rpccorsdomain "*" console -networkid networkID1,2,3 IDE3()Web3 Provider contract CallOption{ address public buyer; address public seller; uint public btc_amount; uint public btc_price; uint public premium; uint public exercise_date; mapping (address => uint) public balanceOfJPY; mapping (address => uint) public balanceOfBTC; function CallOption( address _seller, uint _seller_jpy, uint _seller_btc, uint _btc_price, uint _btc_amount, uint _premium, uint _exercise_date ){ seller = _seller; balanceOfJPY[seller] = _seller_jpy; balanceOfBTC[seller] = _seller_btc; btc_price = _btc_price; btc_amount = _btc_amount; premium = _premium; exercise_date = _exercise_date; } function Respond (address _buyer, uint _buyer_jpy) { buyer = _buyer; balanceOfJPY[buyer] = _buyer_jpy; if (balanceOfJPY[buyer] < premium + btc_amount * btc_price) throw; balanceOfJPY[buyer] -= premium; balanceOfJPY[seller] += premium; } function Expire (uint _current_btc_price, uint _current_time){ if (_current_time < exercise_date) throw; if (_current_btc_price < btc_price) throw; balanceOfJPY[buyer] -= btc_price * btc_amount; balanceOfJPY[seller] += btc_price * btc_amount; balanceOfBTC[buyer] += btc_amount; balanceOfBTC[seller] -= btc_amount; } function () { throw; }} 1Create ContractBlockchainContract 2ExpireRespondContract Continue reading >>

Solidity Tutorials | Ethereum Builder's Guide

Solidity Tutorials | Ethereum Builder's Guide

Solidity is a high-level language whose syntax is similar to that of JavaScript and it is designed to compile to code for the Ethereum Virtual Machine. Thistutorial provides a basic introduction to Solidity and assumes some knowledge ofthe Ethereum Virtual Machine and programming in general. For more details,please see the Solidity specficiation (yet to be written). This tutorial does not cover features likethe natural language documentation or formal verification and is also not meant as a final specificationof the language. You can start using Solidity in your browser ,with no need to download or compile anything. This application only supportscompilation - if you want to run the code or inject it into the blockchain, youhave to use a client like AlethZero. contract SimpleStorage { uint storedData; function set(uint x) { storedData = x; } function get() constant returns (uint retVal) { return storedData; }} uint storedData declares a state variable called storedData of type uint(unsigned integer of 256 bits) whose position in storage is automaticallyallocated by the compiler. The functions set and get can be used to modifyor retrieve the value of the variable. contract Coin { address minter; mapping (address => uint) balances; function Coin() { minter = msg.sender; } function mint(address owner, uint amount) { if (msg.sender != minter) return; balances[owner] += amount; } function send(address receiver, uint amount) { if (balances[msg.sender] < amount) return; balances[msg.sender] -= amount; balances[receiver] += amount; } function queryBalance(address addr) constant returns (uint balance) { return balances[addr]; }} This contract introduces some new concepts. One of them is the address type,which is a 160 bit value that does not allow any arithmetic operations.Furth Continue reading >>

Local Development Environment

Local Development Environment

Let's set up the local environment for smart contract application development. For local development, this tutorial uses the following environment. If you prefer other development tools, please use those as you find appropriate. In this tutorial we will assume contracts will be implemented in Browser Solidity. Execute the following command to download browser-solidity to any folder locally. (You may use this IDE directly from the Browser Solidity website, but it will not be possible to access the Deploy server.) $ git clone -b gh-pages You can start development after you opening the above file in a browser. Prepare BlockExplorer to check the state of blocks on Ethereum. As of this writing, this does not seem to work in Windows environment. Please create a virtual environment with Vagrant etc. for BlockExplorer. Follow the procedure below to launch EtherBlockExplorer. $ git clone cd ./explorer$ npm install bower$ npm start With PortForward setting configured to Deploy node, You can check the status of blocks by accessing the above link. geth -rpc -rpccorsdomain " Continue reading >>

Github - Ethereum/browser-solidity: Browser-only Solidity Ide And Runtime Environment

Github - Ethereum/browser-solidity: Browser-only Solidity Ide And Runtime Environment

Browser-Only Solidity IDE and Runtime Environment Remix (aka. Browser-Solidity) is a browser-based Solidity compiler and IDE. Visit to use;it will always deliver the latest version. The gh-pages branch always has the latest stable build of Remix. It also contains a ZIP file with the entire build. Download it to use offline. Note: it contains the latest release of Solidity available at the time of the packaging. No other compiler versions are supported. Install npm and node.js (see ), then do: git clone npm install - fetch dependencies & executes npm run prepublish to build the application Run npm start and open in your browser. Then open your text editor and start developing.The browser will automatically refresh when files are saved Here are some things to consider if you have trouble building the package. Make sure that you have the correct version of node, npm and nvm. You can find the version that is tested on Travis CI by looking at the log in the build results . In Debian based OSes such as Ubuntu 14.04LTS you may need to run apt-get install build-essential. After installing build-essential run npm rebuild. Register new unit test files in test/index.js.The tests are written using tape . For local headless browser tests run npm run test-browser(Requires selenium to be installed - can be done with npm run selenium-install) Running unit tests via npm test requires at least node v7.0.0 To run the Selenium tests via Nightwatch serve the app through a local web server: npm run serve # starts web server at localhost:8080 Have a Selenium server running locally on port 4444. Run: sc -u -k (see .travis.yml for values) If you would like to use this as a Chrome extension, you must either build it first or pull from the gh-pages branch, both described above.After t Continue reading >>

More in ethereum