Eval/evalnot keywords

[Crimson Wizard]

What do eval and evalnot keywords mean in declaration of actions (decorate).
Example:

Code: Select all

action native A_ExtChase(eval bool usemelee, eval bool usemissile,
      optional evalnot bool playactive, optional eval bool nightmarefast);

[Janis Legzdinsh]

For vavoom nothing, they were added for ZDoom compatibility, but since ZDoom got rid of them, I most likely will also get rid of them soon.