Contract with Fixed Point and non-Fixed Point ints

[joaomontenegro]

How to approach a contract that has some uint256 member variables as fixed point (via PRBMathUD60x18) and some other variables that non-fixed point uint256 integers (via, for example, SafeMath)?

[PaulRBerg]

First way is to use the PRBMathSD59x18Typed.sol and PRBMathUD60x18Typed.sol flavours of PRBMath.

A second way, if you intend to use the vanilla flavours of the library, is to group the fixed-point types within structs, so that I know that if I ever use that struct, all of its containing integers are fixed-point numbers. E.g. here.

A third way, mentioned by @definim in #29, is to use a different nomenclature for the fixed-point variables. E.g. he used Hungarian notation.

Update for PRBMath v3.0.0:

Type safety is now offered via user defined value types SD59x18 and UD60x18. You differentiate fixed-point from non-fixed-point types by simply declaring your variable with the value type (in fact, you must do this in V3, there is no way around it, as I have explained in this separate discussion #143).

[PaulRBerg]

Hey @joaomontenegro, I have recently released PRBMath V3, which is exactly what you were looking for when you posted this question in August 2021 :)

[joaomontenegro]

Awesome! Thank you!