Layout &layout = train.get_layout();
layout.signal_block_reserved.connect(sigc::mem_fun(this, &BlockAllocator::block_reserved));
layout.signal_sensor_state_changed.connect(sigc::mem_fun(this, &BlockAllocator::sensor_state_changed));
Layout &layout = train.get_layout();
layout.signal_block_reserved.connect(sigc::mem_fun(this, &BlockAllocator::block_reserved));
layout.signal_sensor_state_changed.connect(sigc::mem_fun(this, &BlockAllocator::sensor_state_changed));