Now I know we haven't actually written that much code, but we've gone over a ton, so I want to do a quick review. In order for a function to receive native blockchain tokens like Ethereum, you need to mark that function as payable. If you want to force a transaction to do

something and you want it to fail if that wasn't done, you can use a require statement. A transaction that reverts means it undoes any work that it did previously and returns any gas to the user. To get the value sent with a transaction, you can use the Solidity

global message.value. Chainlink is a technology for getting external data and computation into our smart contracts and most importantly getting that data in a decentralized context. In this example, we're going to be using a Chainlink data feed or a Chainlink price feed, which is a

decentralized way to get pricing information from real-world assets into our smart contracts.

Lesson 4 Part 6 | Quick Recap - Solidity & Foundry Full Course

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Functions receiving native tokens need the 'payable' modifier.

'require' statements enforce transaction conditions; failure reverts the transaction.

Reverted transactions undo work and return gas.

Use `msg.value` to access the value sent in a transaction.

Introduction to Chainlink for Smart Contracts

Chainlink enables decentralized data and computation in smart contracts.

Chainlink price feeds provide decentralized pricing information for real-world assets.