\DOC butlast

\TYPE {butlast : 'a list -> 'a list}

\SYNOPSIS
Computes the sub-list of a list consisting of all but the last element.

\DESCRIBE
{butlast [x1,...,xn]} returns {[x1,...,x(n-1)]}.

\FAILURE
Fails if the list is empty.

\SEEALSO
Lib.last, Lib.el, Lib.front_last.
\ENDDOC