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Amy's Vue on this
Amy's Vue on this

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Web3 Solidity + JavaScript 32 hour course recap #11

timestamps: 3:57:00 - 4:11:11

This is a recap of me making my way through the 32 hour course by Patrick Collins posted on FreeCodeCamp.

The first thing that we talked about is the fact that Oracle networks take ERC-20.

I then took it up on myself to look up the different Ethereum protocols (the gemini resource)[https://www.gemini.com/cryptopedia/ethereum-token-standards-erc777-erc1155-erc223-erc1337#section-what-is-erc-1155]

I'm pretty sure that ERC-20, ERC-721, and ERC-1155 are the only ones that I need to be aware of for now.

Chainlink is a technology for getting external data in a decentralized manner.

When interacting with another contract; you need both the address and the ABI. The address can be found in the chainlink documentation, but the ABI is found as an interface in the chainlink npm package. Solidity apparently is "smart enough" to be able to make calls to npm the find files.

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";

and

address ethToUsdAddress = 0x8A753747A1Fa494EC906cE90E9f37563A8AF630e;
AggregatorV3Interface(ethToUsdAddress).version();

are both pretty much what I would expect this to look like.

One side note: I was in Kovan when running the test, but we had copied the Rinkeby wallet address. So make sure that your metamask token selection matches what you're wanting to use.

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