Wiki

trigger · can_construct_building

Definition

  • Supported scope:STATE
  • Supported target:none

Description

Checks if the country (as ROOT) and state in scope can build a building in the state.
ex:
GER = {
	65 = {
		can_construct_building = land_facility
	}
}

Hands-On Notes

Hands-on notes are AI-generated and checked against the vanilla command vocabulary — treat them as a starting point, not authoritative reference. The definition above is the game's own documentation.

Hands-On Usage

can_construct_building is commonly used within the available block of decisions or focuses to pre-validate whether the target state and country meet the construction requirements before triggering building-related rewards, preventing invalid construction after script execution. For example, in an "Industrialization Plan" decision, players are only allowed to click if the state truly permits factory construction:

available = {
    GER = {
        65 = {
            can_construct_building = industrial_complex
        }
    }
}

Synergy

  • [free_building_slots](/wiki/trigger/free_building_slots): Works in conjunction with can_construct_building to further confirm that the target state has sufficient remaining building slots, providing dual insurance against construction failure.
  • [add_building_construction](/wiki/effect/add_building_construction): Typically serves as the effect execution body after can_construct_building conditions are met, responsible for actually queuing the construction task.
  • [is_owned_and_controlled_by](/wiki/trigger/is_owned_and_controlled_by): Construction operations often require the state to be both owned and controlled by the target country; pairing with this trigger ensures complete prerequisites.
  • [has_state_category](/wiki/trigger/has_state_category): Different state categories determine the upper limit of available building slots; combined use filters for high-tier states with construction potential.

Common Pitfalls

  1. Incorrect Scope Nesting: This trigger must be called within STATE scope, with an outer layer switching to the corresponding country scope (as ROOT). Beginners often write can_construct_building directly under country scope, causing game errors or conditions that never fire. Always follow official examples by switching to the country scope first, then nesting the state scope.
  2. Confusing Trigger and Effect: can_construct_building only performs validation; it does not actually start construction. Some players mistakenly believe that once conditions are met, buildings automatically queue, but in reality you must additionally call add_building_construction within the effect block to produce construction behavior.