From: "Jonathan Turkanis" <technews@kangaroologic.com>
"Rob Stewart" <stewart@sig.com> wrote in message news:200409101906.i8AJ6M921012@lawrencewelk.systems.susq.com...
From: "Jonathan Turkanis" <technews@kangaroologic.com>
enum { f_open = 1, f_input_closed = f_open << 1, f_output_closed = f_input_closed << 1, f_output_buffered = f_output_closed << 1 };
This is a pain to read and maintain. You should write them like this:
enum { f_open = 1<<0, f_input_closed = 1<<1, f_output_closed = 1<<2, f_output_buffered = 1<<3 };
I stole this idiom from John Maddock: http://tinyurl.com/4no5s. It's supposed to make insertion in the middle easier. I think it's the vector vs. list tradeoff.
It fails to make insertion in the middle easy, at least comparatively. Start with: Yours/John's Mine enum { name_a = 1, 1<<0, name_b = name_a << 1, 1<<1, name_c = name_b << 1 1<<2 }; Now add name_x after name_b: enum { name_a = 1, 1<<0, name_b = name_a << 1, 1<<1, name_x = name_b << 1, 1<<2, name_c = name_x << 1 1<<3 }; Your version requires a more extensive change due to the use of the enumerator name and makes it harder to determine if the new order is, in fact, sequential. -- Rob Stewart stewart@sig.com Software Engineer http://www.sig.com Susquehanna International Group, LLP using std::disclaimer;