-: and :- are not the same... Maybe some typos... But your list shows how left and right terms are the same in each identities. Look like some pedagogical stuff.
For instance :
(],[) -: ([,])~
(],[) Appends right and left term while ([,])~ append left and right term after arguments order inversion.
For instance :
(],[) -: ([,])~
(],[) Appends right and left term while ([,])~ append left and right term after arguments order inversion.