\DOC

\TYPE {lhand : term -> term}

\SYNOPSIS
Returns the left-hand argument of a binary application.

\DESCRIBE
A call to {lhand t} returns {x} in those situations where {t} is of
the form {``f x y``}.

\FAILURE
Fails if the argument is not of the required form.

\EXAMPLE
{
- lhand ``3 + 2``;
> val it = ``3`` : term
}

\COMMENTS
The name {lhand} is an abbreviation of ``left-hand'', but {rand} is
so-named as an abbreviation of ``operand''.  Nonetheless, {rand} does
return the right-hand argument of a binary application.

\SEEALSO
Term.rand, Term.rator.

\ENDDOC