\DOC rand

\TYPE {rand : term -> term}

\SYNOPSIS
Returns the operand from a combination (function application).

\DESCRIBE
If {M} is a combination, i.e., has the form {(t1 t2)}, then
{rand M} returns {t2}.

\FAILURE
Fails if {M} is not a combination.

\SEEALSO
Term.rator, Term.dest_comb.
\ENDDOC