view libinterp/parse-tree/pt-walk.cc @ 31605:e88a07dec498 stable

maint: Use macros to begin/end C++ namespaces. * oct-conf-post-public.in.h: Define two macros (OCTAVE_BEGIN_NAMESPACE, OCTAVE_END_NAMESPACE) that can be used to start/end a namespace. * mk-opts.pl, build-env.h, build-env.in.cc, __betainc__.cc, __contourc__.cc, __dsearchn__.cc, __eigs__.cc, __expint__.cc, __ftp__.cc, __gammainc__.cc, __ichol__.cc, __ilu__.cc, __isprimelarge__.cc, __lin_interpn__.cc, __magick_read__.cc, __pchip_deriv__.cc, __qp__.cc, amd.cc, auto-shlib.cc, auto-shlib.h, balance.cc, base-text-renderer.cc, base-text-renderer.h, besselj.cc, bitfcns.cc, bsxfun.cc, c-file-ptr-stream.cc, c-file-ptr-stream.h, call-stack.cc, call-stack.h, ccolamd.cc, cellfun.cc, chol.cc, colamd.cc, colloc.cc, conv2.cc, daspk.cc, dasrt.cc, dassl.cc, data.cc, data.h, debug.cc, defaults.cc, defaults.h, defun-int.h, defun.cc, det.cc, dirfns.cc, display.cc, display.h, dlmread.cc, dmperm.cc, dot.cc, dynamic-ld.cc, dynamic-ld.h, eig.cc, ellipj.cc, environment.cc, environment.h, error.cc, error.h, errwarn.h, event-manager.cc, event-manager.h, event-queue.cc, event-queue.h, fcn-info.cc, fcn-info.h, fft.cc, fft2.cc, fftn.cc, file-io.cc, filter.cc, find.cc, ft-text-renderer.cc, ft-text-renderer.h, gcd.cc, getgrent.cc, getpwent.cc, getrusage.cc, givens.cc, gl-render.cc, gl-render.h, gl2ps-print.cc, gl2ps-print.h, graphics-toolkit.cc, graphics-toolkit.h, graphics.cc, graphics.in.h, gsvd.cc, gtk-manager.cc, gtk-manager.h, hash.cc, help.cc, help.h, hess.cc, hex2num.cc, hook-fcn.cc, hook-fcn.h, input.cc, input.h, interpreter-private.cc, interpreter-private.h, interpreter.cc, interpreter.h, inv.cc, jsondecode.cc, jsonencode.cc, kron.cc, latex-text-renderer.cc, latex-text-renderer.h, load-path.cc, load-path.h, load-save.cc, load-save.h, lookup.cc, ls-ascii-helper.cc, ls-ascii-helper.h, ls-oct-text.cc, ls-utils.cc, ls-utils.h, lsode.cc, lu.cc, mappers.cc, matrix_type.cc, max.cc, mex-private.h, mex.cc, mgorth.cc, nproc.cc, oct-fstrm.cc, oct-fstrm.h, oct-hdf5-types.cc, oct-hdf5-types.h, oct-hist.cc, oct-hist.h, oct-iostrm.cc, oct-iostrm.h, oct-opengl.h, oct-prcstrm.cc, oct-prcstrm.h, oct-procbuf.cc, oct-procbuf.h, oct-process.cc, oct-process.h, oct-stdstrm.h, oct-stream.cc, oct-stream.h, oct-strstrm.cc, oct-strstrm.h, oct-tex-lexer.in.ll, oct-tex-parser.yy, ordqz.cc, ordschur.cc, pager.cc, pager.h, pinv.cc, pow2.cc, pr-flt-fmt.cc, pr-output.cc, procstream.cc, procstream.h, psi.cc, qr.cc, quad.cc, quadcc.cc, qz.cc, rand.cc, rcond.cc, regexp.cc, schur.cc, settings.cc, settings.h, sighandlers.cc, sighandlers.h, sparse-xdiv.cc, sparse-xdiv.h, sparse-xpow.cc, sparse-xpow.h, sparse.cc, spparms.cc, sqrtm.cc, stack-frame.cc, stack-frame.h, stream-euler.cc, strfind.cc, strfns.cc, sub2ind.cc, svd.cc, sylvester.cc, symbfact.cc, syminfo.cc, syminfo.h, symrcm.cc, symrec.cc, symrec.h, symscope.cc, symscope.h, symtab.cc, symtab.h, syscalls.cc, sysdep.cc, sysdep.h, text-engine.cc, text-engine.h, text-renderer.cc, text-renderer.h, time.cc, toplev.cc, tril.cc, tsearch.cc, typecast.cc, url-handle-manager.cc, url-handle-manager.h, urlwrite.cc, utils.cc, utils.h, variables.cc, variables.h, xdiv.cc, xdiv.h, xnorm.cc, xnorm.h, xpow.cc, xpow.h, __delaunayn__.cc, __fltk_uigetfile__.cc, __glpk__.cc, __init_fltk__.cc, __init_gnuplot__.cc, __ode15__.cc, __voronoi__.cc, audiodevinfo.cc, audioread.cc, convhulln.cc, fftw.cc, gzip.cc, mk-build-env-features.sh, mk-builtins.pl, cdef-class.cc, cdef-class.h, cdef-fwd.h, cdef-manager.cc, cdef-manager.h, cdef-method.cc, cdef-method.h, cdef-object.cc, cdef-object.h, cdef-package.cc, cdef-package.h, cdef-property.cc, cdef-property.h, cdef-utils.cc, cdef-utils.h, ov-base.cc, ov-base.h, ov-bool-mat.cc, ov-builtin.h, ov-cell.cc, ov-class.cc, ov-class.h, ov-classdef.cc, ov-classdef.h, ov-complex.cc, ov-fcn-handle.cc, ov-fcn-handle.h, ov-fcn.h, ov-java.cc, ov-java.h, ov-mex-fcn.h, ov-null-mat.cc, ov-oncleanup.cc, ov-struct.cc, ov-typeinfo.cc, ov-typeinfo.h, ov-usr-fcn.cc, ov-usr-fcn.h, ov.cc, ov.h, octave.cc, octave.h, mk-ops.sh, op-b-b.cc, op-b-bm.cc, op-b-sbm.cc, op-bm-b.cc, op-bm-bm.cc, op-bm-sbm.cc, op-cdm-cdm.cc, op-cell.cc, op-chm.cc, op-class.cc, op-cm-cm.cc, op-cm-cs.cc, op-cm-m.cc, op-cm-s.cc, op-cm-scm.cc, op-cm-sm.cc, op-cs-cm.cc, op-cs-cs.cc, op-cs-m.cc, op-cs-s.cc, op-cs-scm.cc, op-cs-sm.cc, op-dm-dm.cc, op-dm-scm.cc, op-dm-sm.cc, op-dm-template.cc, op-dms-template.cc, op-fcdm-fcdm.cc, op-fcm-fcm.cc, op-fcm-fcs.cc, op-fcm-fm.cc, op-fcm-fs.cc, op-fcn.cc, op-fcs-fcm.cc, op-fcs-fcs.cc, op-fcs-fm.cc, op-fcs-fs.cc, op-fdm-fdm.cc, op-fm-fcm.cc, op-fm-fcs.cc, op-fm-fm.cc, op-fm-fs.cc, op-fs-fcm.cc, op-fs-fcs.cc, op-fs-fm.cc, op-fs-fs.cc, op-i16-i16.cc, op-i32-i32.cc, op-i64-i64.cc, op-i8-i8.cc, op-int-concat.cc, op-m-cm.cc, op-m-cs.cc, op-m-m.cc, op-m-s.cc, op-m-scm.cc, op-m-sm.cc, op-mi.cc, op-pm-pm.cc, op-pm-scm.cc, op-pm-sm.cc, op-pm-template.cc, op-range.cc, op-s-cm.cc, op-s-cs.cc, op-s-m.cc, op-s-s.cc, op-s-scm.cc, op-s-sm.cc, op-sbm-b.cc, op-sbm-bm.cc, op-sbm-sbm.cc, op-scm-cm.cc, op-scm-cs.cc, op-scm-m.cc, op-scm-s.cc, op-scm-scm.cc, op-scm-sm.cc, op-sm-cm.cc, op-sm-cs.cc, op-sm-m.cc, op-sm-s.cc, op-sm-scm.cc, op-sm-sm.cc, op-str-m.cc, op-str-s.cc, op-str-str.cc, op-struct.cc, op-ui16-ui16.cc, op-ui32-ui32.cc, op-ui64-ui64.cc, op-ui8-ui8.cc, ops.h, anon-fcn-validator.cc, anon-fcn-validator.h, bp-table.cc, bp-table.h, comment-list.cc, comment-list.h, filepos.h, lex.h, lex.ll, oct-lvalue.cc, oct-lvalue.h, oct-parse.yy, parse.h, profiler.cc, profiler.h, pt-anon-scopes.cc, pt-anon-scopes.h, pt-arg-list.cc, pt-arg-list.h, pt-args-block.cc, pt-args-block.h, pt-array-list.cc, pt-array-list.h, pt-assign.cc, pt-assign.h, pt-binop.cc, pt-binop.h, pt-bp.cc, pt-bp.h, pt-cbinop.cc, pt-cbinop.h, pt-cell.cc, pt-cell.h, pt-check.cc, pt-check.h, pt-classdef.cc, pt-classdef.h, pt-cmd.h, pt-colon.cc, pt-colon.h, pt-const.cc, pt-const.h, pt-decl.cc, pt-decl.h, pt-eval.cc, pt-eval.h, pt-except.cc, pt-except.h, pt-exp.cc, pt-exp.h, pt-fcn-handle.cc, pt-fcn-handle.h, pt-id.cc, pt-id.h, pt-idx.cc, pt-idx.h, pt-jump.h, pt-loop.cc, pt-loop.h, pt-mat.cc, pt-mat.h, pt-misc.cc, pt-misc.h, pt-pr-code.cc, pt-pr-code.h, pt-select.cc, pt-select.h, pt-spmd.cc, pt-spmd.h, pt-stmt.cc, pt-stmt.h, pt-tm-const.cc, pt-tm-const.h, pt-unop.cc, pt-unop.h, pt-vm-eval.cc, pt-walk.cc, pt-walk.h, pt.cc, pt.h, token.cc, token.h, Range.cc, Range.h, idx-vector.cc, idx-vector.h, range-fwd.h, CollocWt.cc, CollocWt.h, aepbalance.cc, aepbalance.h, chol.cc, chol.h, gepbalance.cc, gepbalance.h, gsvd.cc, gsvd.h, hess.cc, hess.h, lo-mappers.cc, lo-mappers.h, lo-specfun.cc, lo-specfun.h, lu.cc, lu.h, oct-convn.cc, oct-convn.h, oct-fftw.cc, oct-fftw.h, oct-norm.cc, oct-norm.h, oct-rand.cc, oct-rand.h, oct-spparms.cc, oct-spparms.h, qr.cc, qr.h, qrp.cc, qrp.h, randgamma.cc, randgamma.h, randmtzig.cc, randmtzig.h, randpoisson.cc, randpoisson.h, schur.cc, schur.h, sparse-chol.cc, sparse-chol.h, sparse-lu.cc, sparse-lu.h, sparse-qr.cc, sparse-qr.h, svd.cc, svd.h, child-list.cc, child-list.h, dir-ops.cc, dir-ops.h, file-ops.cc, file-ops.h, file-stat.cc, file-stat.h, lo-sysdep.cc, lo-sysdep.h, lo-sysinfo.cc, lo-sysinfo.h, mach-info.cc, mach-info.h, oct-env.cc, oct-env.h, oct-group.cc, oct-group.h, oct-password.cc, oct-password.h, oct-syscalls.cc, oct-syscalls.h, oct-time.cc, oct-time.h, oct-uname.cc, oct-uname.h, action-container.cc, action-container.h, base-list.h, cmd-edit.cc, cmd-edit.h, cmd-hist.cc, cmd-hist.h, f77-fcn.h, file-info.cc, file-info.h, lo-array-errwarn.cc, lo-array-errwarn.h, lo-hash.cc, lo-hash.h, lo-ieee.h, lo-regexp.cc, lo-regexp.h, lo-utils.cc, lo-utils.h, oct-base64.cc, oct-base64.h, oct-glob.cc, oct-glob.h, oct-inttypes.h, oct-mutex.cc, oct-mutex.h, oct-refcount.h, oct-shlib.cc, oct-shlib.h, oct-sparse.cc, oct-sparse.h, oct-string.h, octave-preserve-stream-state.h, pathsearch.cc, pathsearch.h, quit.cc, quit.h, unwind-prot.cc, unwind-prot.h, url-transfer.cc, url-transfer.h : Use new macros to begin/end C++ namespaces.
author Rik <rik@octave.org>
date Thu, 01 Dec 2022 14:23:45 -0800
parents 796f54d4ddbf
children aac27ad79be6
line wrap: on
line source

////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2017-2022 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// 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 3 of the License, 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, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include "pt-all.h"

OCTAVE_BEGIN_NAMESPACE(octave)

  void tree_walker::visit_anon_fcn_handle (tree_anon_fcn_handle& afh)
  {
    tree_parameter_list *parameter_list = afh.parameter_list ();

    if (parameter_list)
      parameter_list->accept (*this);

    tree_expression *expression = afh.expression ();

    if (expression)
      expression->accept (*this);
  }

  void tree_walker::visit_argument_list (tree_argument_list& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_expression *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_arguments_block (tree_arguments_block& blk)
  {
    tree_args_block_attribute_list *attribute_list = blk.attribute_list ();

    if (attribute_list)
      attribute_list->accept (*this);

    tree_args_block_validation_list *validation_list = blk.validation_list ();

    if (validation_list)
      validation_list->accept (*this);
  }

  void tree_walker::visit_args_block_attribute_list (tree_args_block_attribute_list& lst)
  {
    tree_identifier *attribute = lst.attribute ();

    if (attribute)
      attribute->accept (*this);
  }

  void tree_walker::visit_args_block_validation_list (tree_args_block_validation_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_arg_validation (tree_arg_validation& val)
  {
    tree_expression *arg_name = val.identifier_expression ();

    if (arg_name)
      arg_name->accept (*this);

    tree_arg_size_spec *size_spec = val.size_spec ();

    if (size_spec)
      size_spec->accept (*this);

    tree_identifier *class_name = val.class_name ();

    if (class_name)
      class_name->accept (*this);

    tree_arg_validation_fcns *validation_fcns = val.validation_fcns ();

    if (validation_fcns)
      validation_fcns->accept (*this);

    tree_expression *default_value = val.initializer_expression ();

    if (default_value)
      default_value->accept (*this);
  }

  void tree_walker::visit_arg_size_spec (tree_arg_size_spec& spec)
  {
    tree_argument_list *size_args = spec.size_args ();

    if (size_args)
      size_args->accept (*this);
  }

  void tree_walker::visit_arg_validation_fcns (tree_arg_validation_fcns& spec)
  {
    tree_argument_list *fcn_args = spec.fcn_args ();

    if (fcn_args)
      fcn_args->accept (*this);
  }

  void tree_walker::visit_binary_expression (tree_binary_expression& expr)
  {
    tree_expression *op1 = expr.lhs ();

    if (op1)
      op1->accept (*this);

    tree_expression *op2 = expr.rhs ();

    if (op2)
      op2->accept (*this);
  }

  void tree_walker::visit_boolean_expression (tree_boolean_expression& expr)
  {
    visit_binary_expression (expr);
  }

  void tree_walker::visit_compound_binary_expression (tree_compound_binary_expression& expr)
  {
    visit_binary_expression (expr);
  }

  void tree_walker::visit_break_command (tree_break_command&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_colon_expression (tree_colon_expression& expr)
  {
    tree_expression *op1 = expr.base ();

    if (op1)
      op1->accept (*this);

    tree_expression *op3 = expr.increment ();

    if (op3)
      op3->accept (*this);

    tree_expression *op2 = expr.limit ();

    if (op2)
      op2->accept (*this);
  }

  void tree_walker::visit_continue_command (tree_continue_command&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_decl_command (tree_decl_command& cmd)
  {
    tree_decl_init_list *init_list = cmd.initializer_list ();

    if (init_list)
      init_list->accept (*this);
  }

  void tree_walker::visit_decl_elt (tree_decl_elt& cmd)
  {
    tree_identifier *id = cmd.ident ();

    if (id)
      id->accept (*this);

    tree_expression *expr = cmd.expression ();

    if (expr)
      expr->accept (*this);
  }

  void tree_walker::visit_decl_init_list (tree_decl_init_list& lst)
  {
    // FIXME: tree_decl_elt is not derived from tree, so should it
    // really have an accept method?

    for (tree_decl_elt *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_simple_for_command (tree_simple_for_command& cmd)
  {
    tree_expression *lhs = cmd.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    tree_expression *expr = cmd.control_expr ();

    if (expr)
      expr->accept (*this);

    tree_expression *maxproc = cmd.maxproc_expr ();

    if (maxproc)
      maxproc->accept (*this);

    tree_statement_list *list = cmd.body ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_complex_for_command (tree_complex_for_command& cmd)
  {
    tree_argument_list *lhs = cmd.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    tree_expression *expr = cmd.control_expr ();

    if (expr)
      expr->accept (*this);

    tree_statement_list *list = cmd.body ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_spmd_command (tree_spmd_command& cmd)
  {
    tree_statement_list *body = cmd.body ();

    if (body)
      body->accept (*this);
  }

  void tree_walker::visit_octave_user_script (octave_user_script& fcn)
  {
    tree_statement_list *cmd_list = fcn.body ();

    if (cmd_list)
      cmd_list->accept (*this);
  }

  void tree_walker::visit_octave_user_function (octave_user_function& fcn)
  {
    tree_statement_list *cmd_list = fcn.body ();

    if (cmd_list)
      cmd_list->accept (*this);
  }

  void tree_walker::visit_function_def (tree_function_def& fdef)
  {
    octave_value fcn = fdef.function ();

    octave_function *f = fcn.function_value ();

    if (f)
      f->accept (*this);
  }

  void tree_walker::visit_identifier (tree_identifier&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_if_clause (tree_if_clause& cmd)
  {
    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);

    tree_statement_list *list = cmd.commands ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_if_command (tree_if_command& cmd)
  {
    tree_if_command_list *list = cmd.cmd_list ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_if_command_list (tree_if_command_list& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_if_clause *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_switch_case (tree_switch_case& cs)
  {
    tree_expression *label = cs.case_label ();

    if (label)
      label->accept (*this);

    tree_statement_list *list = cs.commands ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_switch_case_list (tree_switch_case_list& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_switch_case *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_switch_command (tree_switch_command& cmd)
  {
    tree_expression *expr = cmd.switch_value ();

    if (expr)
      expr->accept (*this);

    tree_switch_case_list *list = cmd.case_list ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_index_expression (tree_index_expression& expr)
  {
    tree_expression *e = expr.expression ();

    if (e)
      e->accept (*this);

    std::list<tree_argument_list *> arg_lists = expr.arg_lists ();
    std::list<string_vector> arg_names = expr.arg_names ();
    std::list<tree_expression *> dyn_fields = expr.dyn_fields ();

    auto p_arg_lists = arg_lists.begin ();
    auto p_arg_names = arg_names.begin ();
    auto p_dyn_fields = dyn_fields.begin ();

    std::string type_tags = expr.type_tags ();
    int n = type_tags.length ();

    for (int i = 0; i < n; i++)
      {
        switch (type_tags[i])
          {
          case '(':
          case '{':
            {
              tree_argument_list *l = *p_arg_lists;
              if (l)
                l->accept (*this);
            }
            break;

          case '.':
            {
              std::string fn = (*p_arg_names)(0);
              if (fn.empty ())
                {
                  tree_expression *df = *p_dyn_fields;
                  if (df)
                    df->accept (*this);
                }
            }
            break;

          default:
            panic_impossible ();
          }

        p_arg_lists++;
        p_arg_names++;
        p_dyn_fields++;
      }
  }

  void tree_walker::visit_matrix (tree_matrix& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_argument_list *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_cell (tree_cell& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_argument_list *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_multi_assignment (tree_multi_assignment& expr)
  {
    tree_argument_list *lhs = expr.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    tree_expression *rhs = expr.right_hand_side ();

    if (rhs)
      rhs->accept (*this);
  }

  void tree_walker::visit_no_op_command (tree_no_op_command&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_constant (tree_constant&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_fcn_handle (tree_fcn_handle&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_parameter_list (tree_parameter_list& lst)
  {
    auto p = lst.begin ();

    while (p != lst.end ())
      {
        tree_decl_elt *elt = *p++;

        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_postfix_expression (tree_postfix_expression& expr)
  {
    tree_expression *e = expr.operand ();

    if (e)
      e->accept (*this);
  }

  void tree_walker::visit_prefix_expression (tree_prefix_expression& expr)
  {
    tree_expression *e = expr.operand ();

    if (e)
      e->accept (*this);
  }

  void tree_walker::visit_return_command (tree_return_command&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_simple_assignment (tree_simple_assignment& expr)
  {
    tree_expression *lhs = expr.left_hand_side ();

    if (lhs)
      lhs->accept (*this);

    tree_expression *rhs = expr.right_hand_side ();

    if (rhs)
      rhs->accept (*this);
  }

  void tree_walker::visit_statement (tree_statement& stmt)
  {
    tree_command *cmd = stmt.command ();

    if (cmd)
      cmd->accept (*this);
    else
      {
        tree_expression *expr = stmt.expression ();

        if (expr)
          expr->accept (*this);
      }
  }

  void tree_walker::visit_statement_list (tree_statement_list& lst)
  {
    for (tree_statement *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_try_catch_command (tree_try_catch_command& cmd)
  {
    tree_statement_list *try_code = cmd.body ();

    if (try_code)
      try_code->accept (*this);

    tree_identifier *expr_id = cmd.identifier ();

    if (expr_id)
      expr_id->accept (*this);

    tree_statement_list *catch_code = cmd.cleanup ();

    if (catch_code)
      catch_code->accept (*this);
  }

  void tree_walker::visit_unwind_protect_command (tree_unwind_protect_command& cmd)
  {
    tree_statement_list *unwind_protect_code = cmd.body ();

    if (unwind_protect_code)
      unwind_protect_code->accept (*this);

    tree_statement_list *cleanup_code = cmd.cleanup ();

    if (cleanup_code)
      cleanup_code->accept (*this);
  }

  void tree_walker::visit_while_command (tree_while_command& cmd)
  {
    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);

    tree_statement_list *list = cmd.body ();

    if (list)
      list->accept (*this);
  }

  void tree_walker::visit_do_until_command (tree_do_until_command& cmd)
  {
    tree_statement_list *list = cmd.body ();

    if (list)
      list->accept (*this);

    tree_expression *expr = cmd.condition ();

    if (expr)
      expr->accept (*this);
  }

  void tree_walker::visit_superclass_ref (tree_superclass_ref&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_metaclass_query (tree_metaclass_query&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_classdef_attribute (tree_classdef_attribute& attr)
  {
    tree_identifier *id = attr.ident ();

    if (id)
      id->accept (*this);

    tree_expression *expr = attr.expression ();

    if (expr)
      expr->accept (*this);
  }

  void tree_walker::visit_classdef_attribute_list (tree_classdef_attribute_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef_superclass (tree_classdef_superclass&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_classdef_superclass_list (tree_classdef_superclass_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef_property (tree_classdef_property&)
  {
    // FIXME: Should we operate on the tree_arg_validation object or the
    // identifier and expression parts separately?
  }

  void tree_walker::visit_classdef_property_list (tree_classdef_property_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef_properties_block (tree_classdef_properties_block& blk)
  {
    tree_classdef_property_list *property_list = blk.element_list ();

    if (property_list)
      property_list->accept (*this);
  }

  void tree_walker::visit_classdef_methods_list (tree_classdef_methods_list& lst)
  {
    for (auto ov_meth : lst)
      {
        octave_user_function *meth = ov_meth.user_function_value ();

        if (meth)
          meth->accept (*this);
      }
  }

  void tree_walker::visit_classdef_methods_block (tree_classdef_methods_block& blk)
  {
    tree_classdef_methods_list *methods_list = blk.element_list ();

    if (methods_list)
      methods_list->accept (*this);
  }

  void tree_walker::visit_classdef_event (tree_classdef_event&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_classdef_events_list (tree_classdef_events_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef_events_block (tree_classdef_events_block& blk)
  {
    tree_classdef_events_list *events_list = blk.element_list ();

    if (events_list)
      events_list->accept (*this);
  }

  void tree_walker::visit_classdef_enum (tree_classdef_enum&)
  {
    // Nothing to do.
  }

  void tree_walker::visit_classdef_enum_list (tree_classdef_enum_list& lst)
  {
    for (auto *elt : lst)
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef_enum_block (tree_classdef_enum_block& blk)
  {
    tree_classdef_enum_list *enum_list = blk.element_list ();

    if (enum_list)
      enum_list->accept (*this);
  }

  void tree_walker::visit_classdef_body (tree_classdef_body& body)
  {
    for (auto *elt : body.properties_list ())
      {
        if (elt)
          elt->accept (*this);
      }

    for (auto *elt : body.methods_list ())
      {
        if (elt)
          elt->accept (*this);
      }


    for (auto *elt : body.events_list ())
      {
        if (elt)
          elt->accept (*this);
      }

    for (auto *elt : body.enum_list ())
      {
        if (elt)
          elt->accept (*this);
      }
  }

  void tree_walker::visit_classdef (tree_classdef& cdef)
  {
    tree_classdef_attribute_list *attribute_list = cdef.attribute_list ();

    if (attribute_list)
      attribute_list->accept (*this);

    tree_identifier *ident = cdef.ident ();

    if (ident)
      ident->accept (*this);

    tree_classdef_superclass_list *superclass_list = cdef.superclass_list ();

    if (superclass_list)
      superclass_list->accept (*this);

    tree_classdef_body *body = cdef.body ();

    if (body)
      body->accept (*this);
  }

OCTAVE_END_NAMESPACE(octave)