/*

Copyright (C) 1996, 1997 John W. Eaton

This file is part of Octave.

Octave is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

Octave is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with Octave; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#if defined (__GNUG__) && defined (USE_PRAGMA_INTERFACE_IMPLEMENTATION)
#pragma implementation
#endif

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "defun.h"
#include "error.h"
#include "ov.h"
#include "oct-lvalue.h"
#include "pt-id.h"
#include "pt-idx.h"
#include "pt-misc.h"
#include "pt-walk.h"
#include "utils.h"

// If TRUE, print a warning if a function does not define all the
// values in the return list which are expected.
static bool Vwarn_undefined_return_values;

// Parameter lists.

tree_parameter_list::~tree_parameter_list (void)
{
  while (! empty ())
    {
      iterator p = begin ();
      delete *p;
      erase (p);
    }
}

void
tree_parameter_list::mark_as_formal_parameters (void)
{
  for (iterator p = begin (); p != end (); p++)
    {
      tree_identifier *elt = *p;
      elt->mark_as_formal_parameter ();
    }
}

void
tree_parameter_list::initialize_undefined_elements (const std::string& warnfor,
						    int nargout,
						    const octave_value& val)
{
  bool warned = false;

  int count = 0;

  for (iterator p = begin (); p != end (); p++)
    {
      if (++count > nargout)
	break;

      tree_identifier *elt = *p;

      if (! elt->is_defined ())
	{
	  if (Vwarn_undefined_return_values && ! warned)
	    {
	      warned = true;
	      warning ("%s: some elements in list of return values are undefined",
		       warnfor.c_str ());
	    }

	  octave_lvalue tmp = elt->lvalue ();

	  tmp.assign (octave_value::op_asn_eq, val);
	}
    }
}

void
tree_parameter_list::define_from_arg_vector (const octave_value_list& args)
{
  int nargin = args.length ();

  if (nargin <= 0)
    return;

  int expected_nargin = length ();

  iterator p = begin ();

  for (int i = 0; i < expected_nargin; i++)
    {
      tree_identifier *elt = *p++;

      octave_lvalue ref = elt->lvalue ();

      if (i < nargin)
	{
	  if (args(i).is_defined () && args(i).is_magic_colon ())
	    {
	      ::error ("invalid use of colon in function argument list");
	      return;
	    }

	  ref.assign (octave_value::op_asn_eq, args(i));
	}
      else
	ref.assign (octave_value::op_asn_eq, octave_value ());
    }
}

void
tree_parameter_list::undefine (void)
{
  int len = length ();

  iterator p = begin ();

  for (int i = 0; i < len; i++)
    {
      tree_identifier *elt = *p++;

      octave_lvalue ref = elt->lvalue ();

      ref.assign (octave_value::op_asn_eq, octave_value ());
    }
}

octave_value_list
tree_parameter_list::convert_to_const_vector (tree_va_return_list *vr_list)
{
  int nout = length ();

  if (vr_list)
    nout += vr_list->length ();

  octave_value_list retval;
  retval.resize (nout);

  int i = 0;

  for (iterator p = begin (); p != end (); p++)
    {
      tree_identifier *elt = *p;

      retval(i++) = elt->is_defined () ? elt->rvalue () : octave_value ();
    }

  if (vr_list)
    {
      for (tree_va_return_list::iterator p = vr_list->begin ();
	   p != vr_list->end ();
	   p++)
	{
	  retval(i++) = *p;
	}
    }

  return retval;
}

bool
tree_parameter_list::is_defined (void)
{
  bool status = true;

  for (iterator p = begin (); p != end (); p++)
    {
      tree_identifier *elt = *p;

      if (! elt->is_defined ())
	{
	  status = false;
	  break;
	}
    }

  return status;
}

void
tree_parameter_list::accept (tree_walker& tw)
{
  tw.visit_parameter_list (*this);
}

// Return lists.

tree_return_list::~tree_return_list (void)
{
  while (! empty ())
    {
      iterator p = begin ();
      delete *p;
      erase (p);
    }
}

void
tree_return_list::accept (tree_walker& tw)
{
  tw.visit_return_list (*this);
}

static int
warn_undefined_return_values (void)
{
  Vwarn_undefined_return_values
    = check_preference ("warn_undefined_return_values");

  return 0;
}

void
symbols_of_pt_misc (void)
{
  DEFVAR (warn_undefined_return_values, true, warn_undefined_return_values,
    "-*- texinfo -*-\n\
@defvr {Built-in Variable} warn_undefined_return_values\n\
If the value of @code{warn_undefined_return_values} is nonzero,\n\
print a warning if a function does not define all the values in\n\
the return list which are expected.  The default value is 1.\n\
@end defvr");
}

/*
;;; Local Variables: ***
;;; mode: C++ ***
;;; End: ***
*/
