NEW Register for the London Hackathon!

Github Welcome to the Course

Intro to EVM & Precompiles

Origin of the EVM Accounts, Keys, and Addresses Transactions and Blocks Different Versions of EVM

Development Environment Setup

Set Up Development Environment Create Codespaces Codespace in VS Code

Your Own EVM Blockchain

Your Own EVM Blockchain Avalanche CLI Create Your Blockchain Sending Tokens

Genesis Configuration

EVM Configuration Genesis Block Create Your Genesis File Setup Your ChainID Gas Fees and Gas Limit Gas Fees Configuration Configure Gas Fees Initial Token Allocation Build and Run Custom Genesis EVM

Precompiles

What are Precompiles?Why Precompiles?Interact with a Precompile

Hash Function Precompile

Overview Create an MD5 Solidity Interface Generate the Precompile Packing and Unpacking Implement the Precompile ConfigKey, ContractAddress, and Genesis Register Your Precompile Build and Run Interact with Precompile

Calculator Precompile

Overview Create Solidity Interface Generating the Precompile Unpacking Multiple Inputs & Packing Multiple Outputs Implementing Precompile Setting the ConfigKey & ContractAddress Creating Genesis Block with precompileConfig Testing Precompiles via Go Modify Autogenerated Tests Adding Unit Tests Adding Fuzz Tests Testing CalculatorPlus

Stateful Precompiles

What are Stateful Precompiles?Interacting with StringStore Precompile

Stateful Counter Precompile

Creating Counter Precompile Create Solidity Interface Store Data in EVM State Implementing setCounter Read Data From EVM State Implementing getCounter & increment Setting Base Gas Fees of Your Precompile Setting ConfigKey and ContractAddress Initial State Defining Default Values via Golang Defining Default Values via Genesis Testing Your Precompile Build Your Precompile

Implementing setCounter

Learn how to implement the setCounter method.

Having seen how strings are stored in StringStore, its time for us to store integers with Counter. The thought process for this section can be defined as follows:

Define the storage hash for our counter
Implement StoreCounterValue, a helper function which acts like StoreString in the previous
Implement setCounter

Is this guide helpful?

Edit on GitHub Report Issue

Previous

Store Data in EVM State

Next

Read Data From EVM State

On this page

No Headings

Instructors:

Director of Developer Relations

Developer Relations Engineer

Join Telegram Course Chat

Privacy Policy

We respect your privacy and are committed to protecting your personal data. This privacy policy will inform you about how we look after your personal data and tell you about your privacy rights.

Read full policy