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danthorpe / Money

Swift value types for working with money & currency
MIT License
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Multiply and Divide factors should be a non-unit scaler #44

Closed wildthink closed 8 years ago

wildthink commented 8 years ago

Shouldn't the operations support $11.50 * 10 and not $11.50 * $10? You want the same units with addition and subtraction but it doesn't make sense with multiplication and division.

danthorpe commented 8 years ago

Hi @wildthink - thanks for the feedback!

You're are absolutely correct, this should be the expected behavior.

And it should work - here is the code and the tests for that code.

Which means if it doesn't work there is a bug somewhere? Can you share your line of code?

wildthink commented 8 years ago

Yes, that is correct for the Decimal but shouldn't the same Money -> Money operations not be provided / supported? Rather I would think they should be replaced by something like the following instead.

    public func multiplyBy(other: IntegerLiteralType) -> _Money {
        return _Money(decimal.multiplyBy(other))
    }

etc.

danthorpe commented 8 years ago

Well, the operators are defined for all types which conform to DecimalNumberType, and the tests are explicitly testing that for CNY which is a _Money type. So... it should definitely work. Are you using integer literals or integer values - because that might be the issue. If you could screen grab the bit of your code which isn't compiling with the error that would be helpful.

danthorpe commented 8 years ago

Hey, @wildthink I just double checked this with the latest version, v1.6.1:

let someMoney: GBP = 100.00
let multiplier = 2.5
let moreMoney = multiplier * someMoney * 3.5
print("You have even more money: \(moreMoney)")

which gives me:

You have even more money: £875.00

This illustrates multiplying money types by an float and a float literal. The same works with integers.

Happy to help you if you have issues with this, just get back to me. I'm going to close this for now however.