-----Original Message----- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Jake Voytko Sent: 24 May 2007 03:37 To: boost@lists.boost.org Subject: Re: [boost] GSoC project "Visualization of STLContainers as SVG" -setting options using << or .axis_color(red).title_font(14)...
my_graph.line_color(black).point_color(blue).x_range(-10, 10).y_range(0, 5);
Overall, I'm not against letting users use method calls to set parameters of classes.. sometimes, that's what they're there for. However, I don't feel that this is an alternative that is intuitive to users. When a user normally does chaining, like my_vector[0].to_string().find(...), they aren't expecting my_vector[0] to be affected. However, show a beginner the longest cout statement you can think of with as much chaining as you want and they'll understand that it all affects the printout, even if they don't know what a stream is! I feel that the stream operator chaining can immediately be grasped by beginners, as they know that since it looks like cout and file streams, it must affect a file somehow.
I'm surprised by this view of beginners expectations. Using a set function is surely very common. Although chaining is less common, you don't have to chain, you can write: my_graph.line_color(black); my_graph.point_color(blue); ... whose meaning is surely quite obvious? but once you see an example of chaining, I feel it is obvious what to do to save a bit of typing - always popular! Other peoples views on this? Paul PS Your prototype code doesn't permit chaining freely - it would intolerable in real-life use. But I'm sure you will be working on it ;-)