list.slice(0,1) // → [a ]
list.slice(1) // → [ b,c,d,e]
list.slice(1,2) // → [ b ]
re = list.splice(1) // re = [b,c,d,e] list == [a]
re = list.splice(1,2) // re = [b,c] list == [a,d,e]
list.concat([X,Y]) // → [_,_,_,_,_,X,Y]
list.push(X) // list == [_,_,_,_,_,X]
list.unshift(X) // list == [X,_,_,_,_,_]
list.splice(2, 0, X) // list == [_,_,X,_,_,_]
// after -- [_,_,REF,NEW,_,_]
list.splice(list.indexOf(REF)+1, 0, NEW))
// before -- [_,_,NEW,REF,_,_]
list.splice(list.indexOf(REF), 0, NEW))
list.splice(2, 1, X) // list == [a,b,X,d,e]
list.pop() // → e list == [a,b,c,d]
list.shift() // → a list == [b,c,d,e]
list.splice(2, 1) // → [c] list == [a,b,d,e]