Yes, I use mailgun, thank you

No, but because of the reputability that I need I chose a service.

Yes, but it’s too expensive. I chose Mailgun because I already used it with the student offer.

I’m ok with that, but what I mean is that it makes no sense to change the type of the provided variable if in mathematics the type can be the same.

Logic, in math, if you have a real and you round it, it’s always a real not an integer. If we follow your mind with abs(-1) of an integer it should return a unsigned and that makes no sense.