编辑“触发器”（章节）

=== Early out ===

Unless they are being tooltipped, trigger blocks operate on the so-called "early out" principle.

For a trigger block to be true, all triggers within must be true. "early out" means that as soon as a trigger in the block is evaluated as false, the rest of the triggers in that block are not evaluated.

This is useful to avoid errors.

Ex: the following trigger block checks that the current character scope's primary spouse has the same culture as them. To avoid errors, it first checks that the character `has` a spouse to begin with.
<pre>trigger = {
   exists = primary_spouse
   culture = primary_spouse.culture
}</pre>
If <code>exists = primary_spouse</code> is false, the second trigger is not evaluated.

It is also useful for performance optimization. In a trigger block containing multiple triggers, putting the ones most likely to fail first can significantly reduce the number of triggers checked overall.

Ex: this trigger block checks that the current character scope is a player and an independent ruler.
<pre>trigger = {
   is_ai = no
   is_independent_ruler = yes
}</pre>
If this trigger block is evaluated once a year for each character in the game, since most characters in the game are not players, <code>is_ai = no</code> will almost always be false, and the 2nd trigger will almost never be evaluated at all.