name = 'del/3' slug = 'delete an element from list' description = '''\

del(X, L1, L2): the list L2 is obtained from L1 by deleting element X.

?- del(1, [1,2,3], L).
  L = [2,3].
?- del(2, [1,2,3,2,5], L).
  L = [1,3,2,5] ;
  L = [1,2,3,5].
?- del(X, [1,2,3], L).
  X = 1, L = [2,3] ;
  X = 2, L = [1,3] ;
  X = 3, L = [1,2].
''' hint = {}