Value Zero Validation On Non Value Enforcers

[hanzel98]

What?

• Adds the validation for using zero value on enforcers where the execution shouldn't use value at all.

Why?

• This helps with security for users, so they don't need to remember to add an extra value safety check.
• This makes the value validation cheaper in comparison to using the valueLte enforcer

How?

• Reads the execution value, and makes sure that it is set to 0, otherwise revert