How is that better than {“amount”: “10.00”} (which also bypasses all potential floating point parsing issues that your or your counterparty’s JSON library might have)?
replyIt is explicit about the fact that that number of decimal places is part of the data.
replyThe semantics for your string “10.00” are complex - is it considered equal to “10”? To “10.000”? To “10.001”?
A user interacting with an API that uses such a string might make all sorts of assumptions about what it supports.
A user interacting with an API that has an explicit decimal places concept is being told ‘decimals matter! They can vary! Here be dragons!’
> The semantics for your string “10.00” are complex - is it considered equal to “10”?
replyYes, but "10 USD" would be a non-canonical representation and you probably serialized incorrectly.
> To “10.000”?
Yes, but same caveat as above applies.
> To “10.001”?
Obviously not, and any system you'd ever want to use in a financial context will tell you so.