Powell, Gary wrote:
One note about fusion::tuple I/O manipulators:
"The library defines three manipulators for changing the default behavior: Manipulators tuple_open(arg) Defines the character that is output before the first element. tuple_close(arg) Defines the character that is output after the last element. tuple_delimiter(arg) Defines the delimiter character between elements."
Oleg> "Example: Oleg> std::cout << tuple_open('[') << tuple_close(']') << tuple_delimiter(", Oleg> ") << a;" Oleg> I see a usability issue here. I believe that if one needs to Oleg> specify tuple_open then he would need to specify tuple_close too. Oleg> I propose to change tuple manipulators to be: Oleg> 1) tuple_bounds("(", ")") // if need to specify one bound, I Oleg> need to specify both. Oleg> 2) tuple_delimiter(",") // I'm happy with bounds, but Oleg> delimiter should be specified. Oleg> 3) tuple_punc("(", ",", ")") // I should specify all punctuation.
Hmmm. You may be right here, as there could be confusion from the following:
cout << tuple_open('[') << tuple_delimiter(';') << tuple(1,2) << tuple_close(']');
where it would output [1;2) instead of [1;2]
Oleg> furthermore, I believe that these manipulators are more Oleg> general. They could be used with any sequence, not only with tuples. Oleg> May be it should be factored out to separate library and Oleg> named appropriately? Oleg> 1) seq_bounds("(", ")") // if need to specify one bound, I Oleg> need to specify both. Oleg> 2) seq_delimiter(",") // I'm happy with bounds, but delimiter Oleg> should be specified. Oleg> 3) seq_punc("(", ",", ")") // I should specify all punctuation. Oleg> seq stands for sequence.
The issue is that if you use a facet to do punct, it's tied to the type of container.
I apologize for not looking at what the current code does, but the stuff I wrote orginally was tied directly to the tuples.
The code there was originally written by Jaakko Järvi and Jeremiah Willcock specifically for a tuple TR1 implementation based on a flat (vector style) tuple code that I wrote around 2002. I've since changed it to something generic that can accommodate any sequence type. Yes, I believe that can be factored out into a library (utility) of its own. I agree with the suggestions too. Regards, -- Joel de Guzman http://www.boost-consulting.com http://spirit.sf.net