Assignment Operator

S[i] := x : List, RngIntElt, Elt ->
Redefine the i-th term of the list S to be x. If i ≤0, then an error results. If i = #S + 1, then x is appended to S. Otherwise, if i > #S + 1, an error results. Here i is allowed to be a multi-index.
V2.28, 13 July 2023