Re: [boost] Interest in super string class?

From: Shunsuke Sogame (mb2act_at_[hidden])
Date: 2006-07-04 00:35:26

Jeff Garland wrote:
> Shunsuke Sogame wrote:
>> Jeff Garland wrote:
>>
>> Apart from optimization, the future (under range proposal)
>> 'to_upper' might be:
>>
>>      std::vector<char> const rng;
>>      std::string dst(rng|to_upper);
> 
> Sorta hard for me to anticipate the future ;-) Anyway, I assume rng can be an 
> std::string as well?

'std::string' will be constructed from any "rng"
in the far distant future... :-)
I also can't wait for the future Boost.Range,
I'm working for my own use: http://tinyurl.com/p8e4m
Note that they are not fully implemented yet.

>> The following is possible today:
>>
>>      std::string dst = range_construct(rng|to_upper);
>>      range_copy(rng|to_upper|to_lower|to_upper, dst);
>>
>> Note that '|to_upper' is lazy.
> 
> I have no idea what this code does?  Construct a range from chars that have 
> been upper-cased and write it into dst.  Then copy the rng to while converting 
> it to upper, then lower, then upper?  This one isn't winning me over with code 
> clarity...

'|to_upper' makes a range of 'transform_iterator'.

>> Well, IMHO, I prefer free-functions for another readability:
>>
>>      ::CString rng;
>>      boost::to_upper(rng);
>>
>>      std::vector<char> rng;
>>      boost::to_upper(rng);
>>
>>      super_string str;
>>      str.to_upper(); // !
> 
> In the zero/one argument case there's no significant advantage.  So I'll 
> repeat this case again:
> 
>      std::string s1("foo");
>      std::string s2("bar);
>      std::string s3("foo");
>      //The next line makes me go read the docs again, every time
>      replace_all(s1,s2,s3);  //which string is modified exactly?
> or
>      s1.replace_all(s2, s3);  //obvious which string is modified here
> 
> Of course, you want to be able to work consistently so you have to pull along 
> the functions with less arguments too.

The main problem is that 's1' must be a 'super_string'.
The 'Range' and 'Sequence' abstractions will disappear.
How does this look? :-)

     replace_all(out(s1), in(s2), in(s3));

-- 
Shunsuke Sogame