Re: [boost] boost::dynamic_array

From: Boris (boris_at_[hidden])
Date: 2005-10-04 07:17:43

"Ian McCulloch" <ianmcc_at_[hidden]>, 
news:dhsff0$nb9$1_at_sea.gmane.org...
> Boris wrote:
>
>> "Pavel Vozenilek" <pavel_vozenilek_at_[hidden]>,
>
>>> How would such dynamic_array be better (different) than std::vector?
>>
>> I wouldn't say it's better. It would be just a bit more suitable in a
>> situation where you know that you will deal with a fixed number of
>> elements at runtime. The interface would be probably similar to
>> std::vector but without inserting/removing operations. While std::vector
>> is the natural choice when you need a dynamic array and boost::array when
>> you know the (fixed) size at compile time this new array type (whatever
>> the name would be) would be chosen when you know the (fixed) size only at
>> runtime.
>
> You still have not stated what advantages such a container would have over 
> a
> resizable container.  In other words, if you omit the resize() et. al. 
> from
> std::vector, what extra functionality can be gained in return?

The reason why I don't want to use std::vector in the project I work on is 
that I need a two-dimensional array. Two-dimensional means that the array 
stores not only the length but also width and height. Additionally its 
elements can be accessed with operator()(size_t column, size_t row). Now I 
could derive my two-dimensional array from std::vector but that doesn't make 
much sense because how should the dimensions change when someone calls 
push_back()? A fixed-size array whose size can be set a runtime would be an 
ideal candidate to derive my two-dimensional array from. For all arrays with 
more than one dimension std::vector isn't probably an ideal parent class.

Boris