Re: [boost] Interest in super string class?

From: Jeff Garland (jeff_at_[hidden])
Date: 2006-07-02 18:14:42

Marc Mutz wrote:
> On Sunday 02 July 2006 23:09, Jeff Garland wrote:
>>    basic_super_string trim_copy()       const;
>>    basic_super_string trim_left_copy()  const;
>>    basic_super_string trim_right_copy() const;
>>
>>    basic_super_string to_lower_copy() const;
>>    basic_super_string to_upper_copy() const;
>>
>> I just got tired and didn't add all the variations for replace_xxx.  Of
>> course that makes the interface even fatter :-)
> 
> Right. Therefore I'd make _copy the standard and not provide mutating variants 
> at all. Who needs trim() and trim_copy() (or trimmed(), as I prefer to use 
> English grammar to convey constness of member functions, where possible) if 
> trim() can always be written as s = s.trim_copy()?

I assume you meant

   s = s.trim();

Well, that's very persuasive although I think it's harder to write something 
modifies a collection of objects in place -- no?  Don't get me wrong, I'm 
pretty fond of immutable value types.  Most of date_time is written as 
immutable value types with a couple exceptions.  However, in this case I'm 
building on a base type that's already mutable and it seems to me that it's 
pretty natural to say s.replace_all(...).

>> overloaded  -- how can ET do anything here?
> 
> Well, operators are also mere functions. Instead of implementing a free op+, 
> you implement a member replace() in the ET class, returning another 
> instantiation of the ET, just like op+ would. Granted, it's more work to 
> implement for the plethora of operations, and I can't readily see how to make 
> this specific case of replace() any faster while preserving the ordering of 
> replacements implied in the above (important for '&' in this case), but the 
> point was that this kind of interface is open for these kinds of 
> optimizations, though, on second thought, you could probably do the same 
> thing with the dtor of the ET in the non-const case, too.

I'll take that as a queue to do nothing ;-)

Jeff