def ITE(s, d1, d0, simplify=True):
    """Expression If-Then-Else (ITE) operator

    If *simplify* is ``True``, return a simplified expression.
    """
    s = Expression.box(s).node
    d1 = Expression.box(d1).node
    d0 = Expression.box(d0).node
    y = exprnode.ite(s, d1, d0)
    if simplify:
        y = y.simplify()
    return _expr(y)