new file mode 100644
--- /dev/null
+++ b/src/defun.cc
@@ -0,0 +1,133 @@
+/*
+
+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.
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "defun-int.h"
+#include "ov.h"
+#include "ov-builtin.h"
+#include "ov-mapper.h"
+#include "symtab.h"
+#include "variables.h"
+
+// Install variables and functions in the symbol tables.
+
+void
+install_builtin_mapper (void *mf_arg)
+{
+  octave_mapper *mf = static_cast<octave_mapper *> (mf_arg);
+
+  symbol_record *sym_rec = global_sym_tab->lookup (mf->name (), true);
+
+  unsigned int t
+    = symbol_def::BUILTIN_FUNCTION | symbol_def::MAPPER_FUNCTION;
+
+  sym_rec->unprotect ();
+  sym_rec->define (mf, t);
+  sym_rec->document (mf->doc_string ());
+  sym_rec->make_eternal ();
+  sym_rec->protect ();
+}
+
+void
+install_builtin_function (void *f_arg, const string& name,
+			  const string& doc, bool is_text_fcn)
+{
+  octave_builtin::fcn f = static_cast<octave_builtin::fcn> (f_arg);
+
+  symbol_record *sym_rec = global_sym_tab->lookup (name, true);
+
+  unsigned int t = symbol_def::BUILTIN_FUNCTION;
+
+  if (is_text_fcn)
+    t |= symbol_def::TEXT_FUNCTION;
+
+  sym_rec->unprotect ();
+  sym_rec->define (new octave_builtin (f, name, doc), t);
+  sym_rec->document (doc);
+  sym_rec->make_eternal ();
+  sym_rec->protect ();
+}
+
+static void
+install_builtin_variable_as_function (const string& name,
+				      const octave_value& val,
+				      bool protect, bool eternal,
+				      const string& help)
+{
+  symbol_record *sym_rec = global_sym_tab->lookup (name, true);
+  sym_rec->unprotect ();
+
+  string tmp_help = help.empty () ? sym_rec->help () : help;
+
+  sym_rec->define_as_fcn (val);
+
+  sym_rec->document (tmp_help);
+
+  if (protect)
+    sym_rec->protect ();
+
+  if (eternal)
+    sym_rec->make_eternal ();
+}
+
+void
+install_builtin_variable (const string& name, const octave_value& value,
+			  bool install_as_function, bool protect,
+			  bool eternal, void *sv_fcn_arg,
+			  const string& help_string)
+{
+  symbol_record::sv_function sv_fcn
+    = static_cast<symbol_record::sv_function> (sv_fcn_arg);
+
+  if (install_as_function)
+    install_builtin_variable_as_function (name, value, protect,
+					  eternal, help_string);
+  else
+    bind_builtin_variable (name, value, protect, eternal,
+			   sv_fcn, help_string);
+}
+
+void
+alias_builtin (const string& alias, const string& name)
+{
+  symbol_record *sr_name = global_sym_tab->lookup (name);
+
+  if (! sr_name)
+    panic ("can't alias to undefined name!");
+
+  symbol_record *sr_alias = global_sym_tab->lookup (alias, true);
+
+  if (sr_alias)
+    sr_alias->alias (sr_name);
+  else
+    panic ("can't find symbol record for builtin function `%s'",
+	   alias.c_str ());
+}
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; End: ***
+*/