allow ranges to be disabled * ov.cc, ov.h: Allow creation of range object to be disabled. Also allow range objects to be forced, even when generally disabled. * pt-exp.h (tree_expression::for_cmd_expr): New member variable. (tree_expression::mark_as_for_cmd_expr, tree_expression::is_for_cmd_expr): New functions. * oct-parse.in.yy: Mark for command expressions. * pt-colon.cc (tree_colon_expression::make_range): Force creation of range if expression is a for command expression. * basics.txi, numbers.txi: Document changes.

--- a/libinterp/parse-tree/oct-parse.in.yy
+++ b/libinterp/parse-tree/oct-parse.in.yy
@@ -2571,6 +2571,8 @@
 
   if (end_token_ok (end_tok, parfor ? token::parfor_end : token::for_end))
     {
+      expr->mark_as_for_cmd_expr ();
+
       octave_comment_list *tc = lexer.comment_buf.get_comment ();
 
       lexer.looping--;