// A C++ version of the LISP LENGTH Function.
//
// File:	length.cc
// Author:	course
// Version:	1

#include "lisp.h"

// Returns the length of a list.  Calls error for dotted
// lists.
//
	int
length (object * list)
{
    int	len = 0;
    
    cons * clist;
    while (clist = may_be_cons (list))
    {
	len++;
	list = cdr (clist);
    }
    if ( ! null (list))
	error ( "LENGTH: Unexpected dot construction: ",
		list );
    return len;
}