# Palindrome fold/unfold declarations - The Art of Prolog Chapter 18

PREFIX p: <http://josd.github.io/eye/reasoning/preduction#>
PREFIX : <http://josd.github.io/eye/reasoning#>

{(?Xs) :accept true} p:should_fold {(?Xs) :palindrome true}.
{(?Q ?Xs ?Q1) :accept true} p:should_fold {(?Q ?Xs ?Q1) :palindrome true}.

{(?A) :initial true} p:should_unfold true.
{(?A) :final true} p:should_unfold true.
{(?A ?B ?C ?D ?E) :delta true} p:should_unfold true.
