* HOL/Library: a collection of generic theories to be used together
with main HOL; the theory loader path already includes this directory
by default; the following existing theories have been moved here:
HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
(as While_Combinator);
Sep = List +
consts sep :: "'a * 'a list => 'a list"
recdef sep "measure (%(a,xs). length xs)"
"sep(a, []) = []"
"sep(a, [x]) = [x]"
"sep(a, x#y#zs) = x # a # sep(a,y#zs)"
end