*/ private readonly array $fields; /** * @no-named-arguments * * @param list $propagators */ public function __construct( private readonly array $propagators, ) { $this->fields = $this->extractFields($this->propagators); } #[\Override] public function fields(): array { return $this->fields; } #[\Override] public function inject(&$carrier, ?PropagationSetterInterface $setter = null, ?ContextInterface $context = null): void { foreach ($this->propagators as $propagator) { $propagator->inject($carrier, $setter, $context); } } #[\Override] public function extract($carrier, ?PropagationGetterInterface $getter = null, ?ContextInterface $context = null): ContextInterface { $context ??= Context::getCurrent(); foreach ($this->propagators as $propagator) { $context = $propagator->extract($carrier, $getter, $context); } return $context; } /** * @param list $propagators * @return list */ private function extractFields(array $propagators): array { return array_values( array_unique( // Phan seems to struggle here with the variadic argument // @phan-suppress-next-line PhanParamTooFewInternalUnpack array_merge( ...array_map( static fn (TextMapPropagatorInterface $propagator) => $propagator->fields(), $propagators ) ) ) ); } }