ublas: deprecated features

From: walter_at_[hidden]
Date: 2001-12-03 10:23:33

Hi all,
 
in the process of developing ublas we recently found two issues. The 
resultion of these issues implicates the deprecation of certain parts 
of the library.
 
We designed and implemented different projection classes for 
expressions and containers. This isn't really neccessary. The 
involved classes are
 
vector_range vs. vector_expression_range,
matrix_row vs. matrix_expression_row,
matrix_column vs. matrix_expression_column and
matrix_range vs. matrix_expression_range.
 
We were able to eliminate the need for projection classes of 
expressions and would therefore like to deprecate the usage of 
vector_expression_range, matrix_expression_row, 
matrix_expression_column and matrix_expression_range.
 
Another somewhat related issue concerns the design of member 
functions vs. free functions to construct projections. Historically 
we supported member functions to construct projections of containers, 
for example
 
matrix<double> m (2, 2);
matrix_range<matrix<double> > mr (m.project (range (0, 1), range (0, 
1)));
 
and free functions to construct projections of expressions, for 
example
 
matrix<double> m (2, 2);
matrix_range<matrix<double> > mr (project (trans (m), range (0, 1), 
range (0, 1)));
 
We would prefer to only support free functions for the construction 
of projections.
 
Pros:
- The interdependence of classes decreases.
- It's easier to extend the design with other proxies, for example 
slices or diagonals.
- The library code gets smaller.
 
Cons:
- We'll lose certain (small) optimizations on compilers, which don't 
support partial template specialization.
 
Any comments?
 
Regards
 
Joerg