Add packing expression functions (#261) #498

Job	Run time
Coverage	4m 25s
Check format	52s
run-examples	10m 13s
build (2d, stable, windows-latest)	6m 14s
build (2d, stable, ubuntu-latest)	11m 10s
build (2d, stable, macos-latest)	4m 59s
build (3d, stable, windows-latest)	7m 2s
build (3d, stable, ubuntu-latest)	11m 6s
build (3d, stable, macos-latest)	5m 28s
build (all, stable, windows-latest)	7m 44s
build (all, stable, ubuntu-latest)	7m 10s
build (all, stable, macos-latest)	6m 24s
	1h 22m 47s

Provide feedback