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Getting started security solidity

Using Safe Math library to prevent from overflows

When your are working with numbers in any programming language you are subject to overflows. An overflow happens when the value of number is bigger than the maximum possible value offered by the machine. For example if you’re using an unsigned integer in Solidiy. The possible values of your variable ranges from 0 to  2^256 […]

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erc20 Getting started solidity

Understand the ERC20 token smart contract

One of the most significant smart contract standard on Ethereum is known as ERC-20, which has emerged as the technical standard used for all smart contracts on the Ethereum blockchain for fungible token implementations. The ERC-20 defines a common list of rules that all Ethereum tokens must adhere to. Consequently, this token standard empowers developers […]

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Getting started solidity

Organize your code and control access to your smart contract with modifiers

This tutorial will cover how to control who can interact with your smart contracts in a smart way using modifiers. You’ll alos learn how to make some part of your code only accessible under specific conditions like for example: only the owner of the smart contract can withdraw the funds. Let’s get back to our […]

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Getting started solidity

Inheritance in Solidity, contracts are classes

In this tutorial, we’ll learn how you can easily use inheritance to organize your code. In object-oriented programming, a class is a blueprint for creating objects (a particular data structure), providing initial values for state (member variables or attributes), and implementations of behavior (member functions or methods). In Solidity, a contract acts like a class. […]

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Getting started solidity

Logging data from smart contracts with events

In Solidity, Events are dispatched signals the smart contracts can fire. DApps, or anything connected to Ethereum JSON-RPC API, can listen to these events and act accordingly. Event can also be indexed, so that the event history is searchable later. In the previous tutorial, we saw how to deploy and interact with your first smart […]

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Getting started solidity

Deploying your first smart contract

I guess you are as excited as us to deploy and interact with your first smart contract on the Ethereum blockchain. Don’t worry, as it’s our fist smart contract, we’ll deploy it on a local test network so it does not cost anything for you to deploy and play as much as you’d like with […]

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Getting started solidity

An introduction to Ethereum

Ethereum is a blockchain that stores and runs programs called smart contracts. A blockchain is a public network of decentralized nodes that process transactions and append them to an ever-growing ledger. Ethereum is not the only blockchain (Bitcoin, Stellar, Tezos…) but it is definitely the most popular blockchain used by most developers and companies. To […]