David Abrahams wrote:
Jeff Garland <jeff@crystalclearsoftware.com> writes:
I guess I have yet to be convinced of the supposed disadvantages. super_string is just as extensible as basic_string.
Only sort of. Noninvasive extensions are relegated to "second class" syntax.
I stand by my original statement: 'super_string is just as extensible as basic_string'. Your comment applies to basic_string as much as super_string. Although I guess there's really nothing stopping someone from deriving from super_string and adding their own nifty functions -- as long as they're stateless. Still, I don't see how the current alternative of having "second class" syntax for all advanced string code is better? And C++ programmers have to deal with the fact that some code may be written in an 'object style' and some in a pure functional style -- that's just life as a C++ programmer.
No, I got it, but I don't know what to do with it. Python chose to leave it out of the string class -- Java chose to provide a simplified interface(just to be clear, there's a Pattern class in JAVA that works with string).
Python also has a pattern class that works with string.
python -c "import re; help(re.compile(''))"
What point are you making here?
I'm just clarifying that in Java all the 'Regex functionality' isn't all embedded in the String class -- but there is a relation between the two. super_string is very similar to the JavaString in that respect.
In Perl it's helped along by language features, but it's essentially built-in using operators.
Most operators in C++ can be implemented as free functions.
I realize -- and perhaps something could be done to emulate a perl-like syntax. But I think there's plenty of people that would be against that idea as enabling even more obscure code -- me among them. I'm open to being convinced, but I think clear function names will end up being superior.
Overall though, I didn't see the motivation for leaving Regex out if I'm going to add other functions to the string type.
Well, you have to stop somewhere. Regex might be a good place because it represents a rather large, complicated, and rather different batch of functionality from the rest of what one gets from string. And it draws in dependencies that not everyone needs.
There's no user cost if they don't use Regex other then processing of a few extra includes on compile.
Linking with more libraries, perhaps?
Nope. basic_superstring is a template, so if you never call a *_regex function you won't need to link in the regex library -- it's a header only dependency. If this weren't the case, I'd agree with you. Jeff