[tsimionescu]

> User A holds digital asset X (such as a valuable domain name "xyz.eth") and User B holds digital asset Y (such as a valuable sum of stablecoin tokens) and these users wish to exchange them in a single public + cryptographically verifiable transaction (i.e. atomic swap), without relying on the trust (and for-profit services) of a third-party escrow agent.

OK, how do they do this? Let's say X has 1M gold in World of Warcraft, and Y has 100M Gil in Final Fantasy XIV. How can X and Y use a blockchain to exchange these atomically?

[mattdesl]

If both assets are defined by the same blockchain protocol, a contract can be written that provides both users the ability to deposit the two assets into it. Only once both assets have been deposited will the atomic swap occur. And at any point before this, a deposit could be safely withdrawn (ie: if other party backs out of deal).

Edit: if your question is “how does this technically look in practice”, here is an example: [1]

[1] https://github.com/niftyhorde/swap.kiwi/blob/master/contract...

[tsimionescu]

You claimed that blockchains solve the problem of atomically transferring digital assets. I gave an example of two digital assets I may like to transfer.

Please tell me how Ethereum solves the problem of exchanging WoW gold for FF14 Gil in a trust less manner.

The problem of transferring digital goods controlled by the same entity in a trust less manner is trivial and solved by many technologies predating Bitcoin. I can already trustlessly sell a piece of copper in World of Warcraft for gold without involving any other third party.

[mattdesl]

This is a pretty stupid argument; WoW and FF14 gold are not assets defined on the network. The goal of Ethereum is to record Ethereum-based assets (e.g. ERC20, ERC721), not to record the exchange of every asset on the web.

> I can already trustlessly sell a piece of copper in World of Warcraft for gold without involving any other third party.

In this case the third party is Blizzard Entertainment, who can control the state and data.

[tsimionescu]

> In this case the third party is Blizzard Entertainment, who can control the state and data.

And in the case of two Ethereum based assets, the third party is the Ethereum network, which can be forked to control the state and data (as it was after the DAO fiasco).

[therealdrag0]

I think more importantly the integration with Ethereum network is done by third parties, so even if WOW hooks into eth, your eth assets are worthless without depending on blizzard to maintain that integration. So what was gained?

[swalsh]

"And in the case of two Ethereum based assets, the third party is the Ethereum network, which can be forked to control the state and data"

ETH Classic still exists, but the community came to the agreement that forking was the best way to deal with the issue. The only person who lost on that agreement was the hacker. Where as Blizzard can do whatever it wants. Surely you can see how a forked blockchain was a more democratic process than a centralized database.

[mattdesl]

A company like Blizzard that might define ERC20WoWGold can fork the blockchain to try and alter a record on their contract, but it would have little effect.

A successful fork requires a consensus across the majority of developers and users in the network.