Disallow new variables in nested functions (bug #36271) * src/ov-usr-fcn.cc (octave_user_function::bind_automatic_vars): Use force_varref. * src/variables.cc (bind_ans): Use force_varref. * src/pt-id.cc (tree_identifier::rvalue, tree_identifier::lvalue): Identify static workspace errors. * src/pt-id.h (tree_identifier::static_workspace_error): New function. * src/symtab.cc (symbol_table::do_update_nest): Mark static workspaces. * src/symtab.h (symbol_table::symbol_record::symbol_record_rep::is_added_static, symbol_table::symbol_record::symbol_record_rep::mark_added_static, symbol_table::symbol_record::symbol_record_rep::unmark_added_static, symbol_table::symbol_record::is_added_static, symbol_table::symbol_record::mark_added_static, symbol_table::symbol_record::unmark_added_static, symbol_table::force_varref): New functions. (symbol_table::symbol_table): Initialize static_workspace to false. (symbol_table::do_insert): Added force_add parameter. Mark records as added_static. (symbol_table::do_varref): Added force_add parameter. * test/nest/test_nest.m: Added nest_eval tests. * test/nest/module.mk: Added nest/nest_eval.m. * test/nest/nest_eval.m: New file.

function x = nest_eval (a, b)
  eval (a);
  nested ();

  function nested ()
    eval (b);
  endfunction
endfunction