Constants are not explicitly declared

[code423n4]

Handle

WatchPug

Vulnerability details

It's a best practice to use constant variables rather than literal values to make the code easier to understand and maintain.

Consider defining a constant variable for the literal value used and giving it a clear and self-explanatory name.

Instances include:

https://github.com/XDeFi-tech/xdefi-distribution/blob/3856a42df295183b40c6eee89307308f196612fe/contracts/XDEFIDistribution.sol#L82-L82

require(duration <= uint256(18250 days), "INVALID_DURATION");

Consider changing uint256(18250 days) to MAX_DURATION constant.

[deluca-mike]

I agree. We will define MAX_DURATION and MAX_BONUS_MULTIPLIER and used them accordingly in the contact.

I actually like this a lot, so I am going to define a ZERO_ADDRESS, ZERO, ONE, and TWO as well, since it will make things a bit clearer, and because so many people kept erroneously claiming that uint256(0) (and the sort) were wasting gas casting, when it is in fact an in-line literal of explicit type.

[deluca-mike]

In release candidate contracts, constants defined here and they are used throughout.