% elp
Standard ML of New Jersey, Version 0.93, February 15, 1993
Elp, Version 0.1x, Built: Fri Jan  7 12:41:04 EST 1994
?- default (searching "/mnt/eniac/home3/d/dale/360/mods/").
solved

yes
?- load "lists".
[reading file /mnt/eniac/home3/d/dale/360/mods/lists.mod]
id : {A:type} list A -> list A -> o.
memb : {A:type} A -> list A -> o.
append : {A:type} list A -> list A -> list A -> o.
memb_and_rest : {A:type} A -> list A -> list A -> o.
[closed file /mnt/eniac/home3/d/dale/360/mods/lists.mod]
solved

yes
?- use "lists".
?- append (1::2::nil) (5::8::nil) L.

L = 1 :: 2 :: 5 :: 8 :: nil.
;
no more solutions
?- 
   append L K (1::2::3::nil).

K = 1 :: 2 :: 3 :: nil,
L = nil.
;

K = 2 :: 3 :: nil,
L = 1 :: nil.
;

K = 3 :: nil,
L = 1 :: 2 :: nil.
;

K = nil,
L = 1 :: 2 :: 3 :: nil.
;
no more solutions
?- append L L (1::2::1::2::nil).

L = 1 :: 2 :: nil.
;
no more solutions
?- memb_and_rest  X (1::3::5::nil) R.

R = 3 :: 5 :: nil,
X = 1.
;

R = 1 :: 5 :: nil,
X = 3.
;

R = 1 :: 3 :: nil,
X = 5.
;
no more solutions
?- solved

yes
?- memb 2 (1::X::Y::6::nil).

Y = Y,
X = 2.
;

Y = 2,
X = X.
;
no more solutions
?- memb 2 L.

L = 2 :: L1.
;

L = Y :: 2 :: L2.
;

L = Y :: Y1 :: 2 :: L3.
;

L = Y :: Y1 :: Y2 :: 2 :: L4.
;

L = Y :: Y1 :: Y2 :: Y3 :: 2 :: L5.

yes
?- memb 2 L, memb 3 L.

L = 2 :: 3 :: L1.
;

L = 2 :: Y :: 3 :: L2.
;

L = 2 :: Y :: Y1 :: 3 :: L3.
;

L = 2 :: Y :: Y1 :: Y2 :: 3 :: L4.

yes
?-