node {
void evaluate(Context ctx) {
// The node responds only if there is an input pulse
if (!isInputDirty<input_UPD>(ctx))
return;
// Get a pointer to the `Adafruit_TSL2591` class instance
auto sensor = getValue<input_DEV>(ctx);
emitValue<output_GAIN>(ctx, sensor->getGain());
emitValue<output_DONE>(ctx, 1);
}
}