Constructing Recursive Data Structures: Lists

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Lists:

• A nonempty list is a head followed by a tail (another list)
• Or the empty list (nil)

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The functor name usually associated with lists is `.'

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The constant name used to denote the empty list is []

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E.g., .(a, .(b, .(c, []))) is the list comprised by the elements a, b, and c

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When some term is a list:

is_list([]).
is_list(.(Head, Tail)):- is_list(Tail).