Question

I’m adding a list and when I use MyArray|MyElement I print to screen and I get:

[obj1,obj2] | obj3

which isn’t correct, is it? Ideally I want it to be:

[Obj1,Obj2,Obj3]

if I use MyArray|[MyElement]printing out gives me:

[Obj1,Obj2] | [Obj3]

is this the equivalent to [Obj1,Obj2,Obj3] ?

Answer 1

Using the syntax [ MyElement | MyArray ], you’d get

[Obj3, Obj1, Obj2]

This is what’s known as “consing” an element onto a list. You could also use an append/3 predicate, like this:

append( MyArray, [MyElement], X).

which produces

X = [Obj1, Obj2, Obj3]