Would it be alright to store the reverse key in addition to the regular key in an exchange?

varunsrin / rusty_money

Money library for Rust

MIT License

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Would it be alright to store the reverse key in addition to the regular key in an exchange? #51

Open JavedNissar opened 3 years ago

JavedNissar commented 3 years ago

If you store a rate for USD -> GBP and then you query for the rate for GBP -> USD, you get a None value. This doesn't seem correct to me. Shouldn't the value returned be 1/(rate returned for USD -> GBP)?

varunsrin commented 3 years ago

yes, the exchange rate crate isn't very mature right now, thanks for pointing out these issues.

i noticed some PR's, will review them over the weekend.

i will probably drop a new release (4.0.1) on Monday with any changes that are ready.

JavedNissar commented 3 years ago

That sounds good, no rush 😄 . I actually probably should add some tests anyways.

DavidBM commented 3 years ago

We found that the rate for USD -> GBP is not the same as the rate for GBP -> USD in the real world exchanges (example: currencylayer.com).

If the crate wants to align with the currency exchanges in the market, it should return None as in the majority of cases you will want to store two different rates.