Quote from: tbct_mt2 on Today at 06:54:21 AM

It makes no sense because the volume of BTC is big and you can not become a whale.

If you are trading in low volume altcoins, you can create both buy and sell orders. Big orders to make them as buy and sell walls. You can control price in your wall areas. Tongue

This is not relevant to the topic.

Quote from: justdimin on Today at 01:55:24 PM

First of all, I don't know why someone would sell 1 BTC for $45k and later buy them for $46k.

This was a hypothetical scenario, I already specified that this scenario is unlikely to occur, however, I wanted to know what the exchange should do if a user places this type of order.

Clearly, it's not in a users best interest, so my question was: should the exchange go out of its way to prevent the user from doing this?
See:

Quote from: c_atlas on May 18, 2021, 09:36:32 PM

Thanks, and I agree, no one would realistically ever do this (unless they wrote a really shitty trading bot and didn't realize it was buggy).

Quote from: justdimin on Today at 01:55:24 PM

You need to understand some facts.

- Market price of a coin is determined by what value it was last traded for (sell or buy)
- Orders you place are filled when that "market price" is reached

Either your reading comprehension is poor, or you didn't bother to read the (short) thread. How do you expect to contribute if you don't know what has been said? See:

Quote from: c_atlas on May 18, 2021, 09:36:32 PM

I've been writing an exchange in my spare time as a learning experience. To test the program, I run a simulation which randomly picks accounts and places orders; I noticed during this time that accounts occasionally fill their own orders, and wasn't sure if this was desirable.

So actually, I "understand [the] facts" quite well, considering I've actually built a functioning electronic exchange.

Quote from: leea-1334 on Today at 06:58:10 AM

Actually,,, the exchanges I have do not let you do it. When you already put the one buy order at the price, and you try to put another sell order at the same price, I remember getting a message saying you are not allowed to do it. Cannot remember which exchange this was but I assumed it was then for all.

Thanks! I think this behaviour actually makes the most sense. Preventing a user from selling lower than their highest buy (or vice versa) before their order is placed on the market seems to be correct.