simple question about Javascript syntax

[ghost]

I meet this syntax in index.js on line: 16 in lesson 8 and it see to me to me more TypeScript as JavaScript. I don't understand what the : after method mean.
It looking to be a key : value in a Object, but witch Object...?

await ethereum.request({ method: "eth_requestAccounts" })

[coinfeigm]

It is a JavaScript syntax (an object argument). It is a wrapper call by ethers-js to the provider function that needs a RequestArguments interface:

interface RequestArguments {
  method: string;
  params?: unknown[] | object;
}

Here is the documentation:
https://docs.ethers.io/v5/api/providers/other/#Web3Provider--ExternalProvider

[ghost]

Thanks @coinfeigm

I think in JavaScript don't exist some kind of declarations as type string.
Only TypeScript have that syntay: lastName : string; // lastName is now of type string

in js we have
let lastName = "John"; // String
or
let lastName = new String("John")

so I think that the interface RequestArguments is a TypeScript interface.

[PatrickAlphaC]

The function request takes an object as an input parameter, we supply that object using JSON notion.

{ method: "eth_requestAccounts" }

The input parameter for the request function is this

[ghost]

Thanks Patrick, now is very clear for me.