newton 49> maple
    |\^/|     Maple V Release 3 (University of Texas - Austin)
._|\|   |/|_. Copyright (c) 1981-1994 by Waterloo Maple Software and the
 \  MAPLE  /  University of Waterloo. All rights reserved. Maple and Maple V
 <____ ____>  are registered trademarks of Waterloo Maple Software.
      |       Type ? for help.
> read ljoin;
> op(ljoin);

proc(x1:list,x2:list) [x1[],x2[]] end

> l1 := [1,2,3];

                                l1 := [1, 2, 3]

> l2 := [3,4,5];

                                l2 := [3, 4, 5]

> ljoin(l1,l2);

                               [1, 2, 3, 3, 4, 5]

>