Tests whether an entity has the selected concrete component type.
Signature
C means a concrete type selector. The result observes the entity's current component set and rejects an unknown entity rather than inventing absence.
Parameters
entity: Entity- An existing entity identity.
Returns
BoolTrue when the entity has component C.
Examples
Test component presence
The selector is required when the function value would otherwise not identify C.
Devices
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main.kj
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Output 0
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State
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Expected output
true
Rust definition
Rust interpreter builtin dispatch; C must name a concrete type and is checked during specialization.
View Rust documentation →Support: runtime