pasman pasmański <pasma...@gmail.com> Sunday 25 of September 2011 15:19:28
> Hi.
> 
> I propose to add "accumulative" flag to a function definition. This
> flag would be set for function f(x) which is accumulative and
> immutable.
> 
> This flag allows to use an index on  x for clauses containing f(x):
> 
> where f(x) = const
I think for this index designe will require that f(x) will be stored, 
additional behaviour of fucntion are not required, is quite enaugh that it 
will be function.

> where f(x) > const
> 
> and so on.
By this assume that "accumulative" function is
(weakly) increasing or decreasing

f such that x < y => f(x) <= f(y)
?

I only may deduce it for idea that search will be faster on index.

Regards,
Radosław Smogura
http://softperience.eu/

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